Vocabulary for Adobe Acrobat | PDFs, Signing & Redaction

Adobe Acrobat vocabulary helps people read, edit, fill, sign and protect PDF documents correctly. Start with PDF, OCR, Fill & Sign, electronic signature, digital signature, certificate, Request e-signatures, redaction, sanitization and PDF/A. These are not merely menu labels: they describe different kinds of document information, authority and risk.

Two distinctions matter most. **Electronic signature versus digital signature:** an electronic signature is a broad way of expressing agreement electronically, while a certificate-based digital signature uses cryptographic identity and integrity checks. **Redaction versus black highlight:** proper redaction removes selected underlying visible data; painting a black shape over text may only conceal what a viewer sees while leaving the content searchable or recoverable.

Quick answer: Use Fill & Sign to complete eligible forms, Request e-signatures to route documents to other people, Acrobat’s certificate tools for qualifying digital signatures and Redact a PDF to remove sensitive visible content. If confidential material may exist in metadata or attachments, sanitize the document as well. Adobe’s October 2026 guidance makes clear that redaction is permanent once applied and saved, so retain an appropriately protected original before the operation.

Read and navigate: page, thumbnail, bookmark, page range and PDF/A.
Create: scan, OCR, compress, combine, split and export.
Complete forms: interactive fields, checkboxes, initials and signatures.
Review: comments, highlights, annotations and accessibility.
Protect: open password, permission restrictions, proper redaction and sanitization.
Preserve evidence: check signature validity, approved versions and audit trails.

This independent guide is intended for readers handling PDFs, not as legal advice on whether one signature type meets a particular law or institution’s acceptance standard. See Vocabulary for Microsoft Word | Documents, Editing and Review Terms Explained for source-document editing vocabulary.

What a PDF contains that the screen may not reveal

Imagine receiving a scanned agreement. It looks like a page of readable words, but Acrobat may initially see it primarily as an image. Running OCR can add searchable or editable text. This is helpful for finding names and copying passages, but recognition can misread small print, numbers and unusual lettering. The correct practice is to compare important results with the visual original.

Now imagine an employer removes a worker’s identity number by drawing a black rectangle over it. The visible page may appear private, yet the underlying text, metadata or embedded files may still exist. Adobe’s official Pro guidance explains that redaction removes selected visible material and sanitization removes hidden content such as metadata. They are separate operations that should be reviewed together.

Finally, a digital signature is not just a picture of handwriting. Acrobat supports certificate-based signing using a digital ID to associate the document with particular signing credentials and detect certain subsequent changes. The certificate’s trust, the signer’s authority and whether the agreement is enforceable under local law are separate matters.

PDF basics and organising pages in Acrobat

The following 36 terms belong to one PDF workflow. Each one includes a realistic example to show why the distinction matters.

PDF

Portable Document Format, a file format designed to represent documents across different devices. Example: Save the approved instructions as a PDF.

Adobe Acrobat

Adobe software for viewing, editing, organising, signing and protecting PDFs under eligible plans. Example: Use Acrobat for an accessible PDF workflow.

Acrobat Reader

Adobe’s PDF viewing application with a selected set of annotation and signing capabilities. Example: Reader does not include every Pro editing feature.

Acrobat Pro

A paid Acrobat offering advanced PDF editing, redaction and other eligible tools. Example: Pro can support proper redaction rather than drawing a black box.

Document

A digital collection of one or more pages or related data. Example: Check every page of the contract.

Page

A unit of the PDF’s document sequence. Example: Locate the signature area on page seven.

Page thumbnail

A small preview used for navigation or arranging pages. Example: Use thumbnails to check page order.

Page range

A specified selection of pages to process or export. Example: Print only pages two through five.

Page number

A count or label identifying a page’s position or numbering scheme. Example: The displayed page number may differ from the printed section number.

Bookmark

An internal navigation pointer to a section or page within a PDF. Example: Add bookmarks to a long report.

Document outline

A structured list of headings or navigation targets within a PDF. Example: An outline can make a large manual easier to use.

Combine files

Merge several eligible source documents into one PDF. Example: Combine the cover letter and evidence into one file.

Merge PDF

Join separate PDF documents or other compatible sources into a single result. Example: Merge carefully so confidential pages are not included.

Split PDF

Divide one PDF into multiple files based on selected rules. Example: Split the manual into individual chapters.

Extract pages

Save selected pages in a separate document under tool permissions. Example: Extract the signed page for a specific filing.

Delete pages

Remove selected pages from a PDF under the permitted editing process. Example: Check page numbers before deletion.

Reorder pages

Change the sequence of existing pages. Example: Move the contents page to the beginning.

Rotate pages

Change the stored orientation of selected pages. Example: Rotate the sideways scan before sharing.

Crop pages

Adjust the displayed page area or boundaries under PDF editing rules. Example: Cropping may hide material without removing underlying content.

Insert pages

Add new pages to an existing PDF. Example: Insert the revised appendix in the correct order.

Replace pages

Substitute selected pages while preserving an intended document structure where supported. Example: Replace the outdated schedule rather than appending it twice.

Organize Pages

An Acrobat tool family for arranging, extracting and modifying PDF pages. Example: Use Organize Pages to inspect all thumbnails.

File size

The storage space required for the PDF. Example: A large scanned file can be difficult to email.

Compress PDF

Reduce an eligible PDF’s file size with potential quality or content trade-offs. Example: Compress the copy but retain the original.

Optimize PDF

Apply selected changes to reduce size or improve efficiency under compatible options. Example: An optimized PDF still needs readability checks.

Image compression

Reduce the data needed to encode images inside a document. Example: Excessive compression can blur small print.

Resolution

The image or scan detail described using pixels or dots per unit. Example: A high-resolution scan can enlarge the document.

DPI

Dots per inch, a common measure for scanning or print-resolution settings. Example: Choose sensible DPI rather than assuming maximum is always best.

Scan to PDF

Create a PDF from paper using a scanner or compatible camera workflow. Example: Scan the signed form for electronic filing.

OCR

Optical character recognition, converting visible text images into a searchable text representation. Example: OCR helps search a photographed contract.

Searchable PDF

A document containing text data that can be searched, sometimes created from scanned images through OCR. Example: Searchable does not guarantee every word was recognised correctly.

Text layer

Machine-readable text stored or inferred within a PDF, separate from the image or page appearance. Example: A text layer can contain OCR errors.

PDF/A

A family of PDF standards intended for long-term archiving under selected conformance rules. Example: PDF/A is not simply another name for a normal PDF.

Document properties

Information describing a PDF’s pages, metadata, security and other characteristics. Example: Check document properties when a file behaves unexpectedly.

Metadata

Information about a file, such as author, creation date or embedded attributes, some of which may be sensitive. Example: Metadata may survive a visual edit.

PDF portfolio

A container format grouping several files within one PDF-based collection under compatible software. Example: A PDF portfolio is not identical to merging every page together.

Filling forms and using signatures

The following 35 terms belong to one PDF workflow. Each one includes a realistic example to show why the distinction matters.

Fill & Sign

An Acrobat workflow for entering text, checkmarks, initials or eligible signature marks on documents. Example: Use Fill & Sign for an ordinary registration form.

Interactive form

A PDF with fields intended to receive typed or selected user input. Example: Click the highlighted box to type a name.

Flat form

A document with printed form areas but no interactive PDF field controls. Example: Fill & Sign can help place text over a flat form.

Text field

A form area intended to receive typed information. Example: Type the complete address in the text field.

Checkbox

A field with a selected or unselected state. Example: Tick only the conditions that actually apply.

Radio button

A form option ordinarily permitting one selection from a defined group. Example: Choose one delivery method using radio buttons.

Dropdown

A field offering a list of eligible choices. Example: Select the correct country from the dropdown.

Required field

A field that must be completed under the form’s validation settings. Example: A missing required field can block submission.

Optional field

An input that may be left empty if not relevant. Example: Do not invent information for an optional field.

Field validation

Rules checking whether entered information matches expected format or criteria. Example: Validation can reject an improperly formatted email address.

Signature field

A designated location for an authorised person to sign the document. Example: Do not place your signature in another person’s field.

Initials

A shortened identifying mark sometimes requested on individual pages. Example: Initial the marked page only when instructed.

Signature appearance

How a signature looks visually on the page. Example: A visible signature image is not the same as proof of cryptographic authenticity.

Electronic signature

An electronic process or mark used to indicate agreement or sign a document under applicable laws and platform rules. Example: An electronic signature’s legal effect depends on circumstances and jurisdiction.

Digital signature

A cryptographic signature based on digital certificates and verification methods. Example: A digital signature can help detect later modification.

Digital ID

An identity-and-key credential used for certificate-based signing under an approved or configured system. Example: Protect the digital ID and its password.

Certificate

A digital credential used to associate verification information with a signer or system. Example: Check the certificate’s trust and validity.

Certificate authority

An entity that issues or manages certificates under specified trust arrangements. Example: A certificate authority’s status affects signature validation.

Self-signed certificate

A certificate issued by the signer rather than an established external authority. Example: Self-signed does not automatically meet an organisation’s trust requirements.

Signature validity

The result of checking a digital signature’s integrity and certificate conditions. Example: A valid signature check does not prove every factual statement in the contract.

Document integrity

Evidence that the signed file has not been altered in certain protected ways. Example: Integrity and legal enforceability are different questions.

Tamper detection

A capability signalling selected unauthorised changes after signing. Example: Read what modifications a signature permits.

Lock document after signing

A digital-signature option to restrict further changes under eligible settings. Example: Locking can prevent later edits to the signed version.

Request e-signatures

An Acrobat service for sending documents to others to sign through supported electronic workflows. Example: Send the final agreement for authorised signatures.

Recipient

A person asked to review or sign a document. Example: Check the recipient’s email address carefully.

Signer

A person assigned to place a signature on an agreement. Example: A signer must understand the document before accepting it.

Signing order

The sequence in which multiple signers are asked to act. Example: Set signing order if the supervisor must sign first.

Agreement

The document and associated signature workflow tracked by an e-signature service. Example: The agreement status can remain In progress.

Agreement status

A label showing whether requested signing remains pending or is complete. Example: A sent request is not a completed agreement.

Reminder

A scheduled notification about an unfinished signature request. Example: A reminder does not replace consent.

Completion deadline

A specified time by which a signature request should be finished. Example: The deadline should be explicit in the invitation.

Audit report

A record of relevant e-signature events under the service’s workflow. Example: An audit report supports review but must be interpreted correctly.

Authentication method

The process used to verify a signer’s identity in an eligible transaction. Example: Email possession may not satisfy every identity requirement.

Signed copy

The document produced after signature actions and processing. Example: Keep the signed copy distinct from the unsigned draft.

Legal acceptance

Whether an electronic signature is valid for the particular transaction and jurisdiction. Example: Not every document type may be signed through the same process.

Reviewing, annotating and making accessible PDFs

The following 35 terms belong to one PDF workflow. Each one includes a realistic example to show why the distinction matters.

Comment

A review note added to a PDF without necessarily replacing the underlying text. Example: Leave a comment on the incorrect figure.

Sticky note

An annotation used for short feedback at a selected position. Example: Use a sticky note to ask for a missing reference.

Highlight

A visual annotation emphasising selected text. Example: Highlight the actual deadline, not the whole paragraph.

Underline

A markup drawing a line beneath selected text. Example: Underline an unfamiliar technical term.

Strikethrough

An annotation indicating text proposed for deletion. Example: Strikethrough is not the same as removing text.

Drawing markup

Freehand or shaped marks added for review. Example: Circle the diagram element under discussion.

Text comment

A typed note relating to a selected location or document part. Example: Explain why a label is misleading.

Reply to comment

A response linked to another person’s review remark. Example: Reply when the revision has been checked.

Resolve comment

Mark a discussion as addressed under review workflow rules. Example: Resolving a comment does not prove the content was corrected.

Review status

A marker such as accepted or rejected under selected annotation processes. Example: Review status is not a legal sign-off by itself.

Shared review

A collaboration workflow letting eligible people contribute PDF feedback. Example: Shared review can reduce competing emailed versions.

Review link

A URL giving selected people access to a commenting or viewing workflow. Example: Inspect link permissions before sending a confidential PDF.

Comment summary

A compiled record of notes or annotations from a review. Example: Use a comment summary to prepare revisions.

Edit PDF

An Acrobat feature for modifying supported PDF text, images or objects rather than merely annotating them. Example: Editing a PDF can affect typography or reflow.

Text reflow

The rearrangement of words around boundaries when a text edit changes layout. Example: Long edits may cause text reflow.

Font substitution

Using another typeface when the original font cannot be edited or embedded correctly. Example: Font substitution can change page breaks.

Embedded font

A font representation stored in the PDF to preserve display under suitable rights and settings. Example: Embedded fonts help consistency across devices.

Accessible PDF

A document designed to be understood through assistive technology as well as visual reading. Example: Accessible PDFs need more than large text.

Tagged PDF

A PDF containing structural tags identifying logical document elements. Example: Tags help screen readers understand reading order.

Reading order

The intended sequence in which content is read through assistive technology. Example: A two-column PDF needs correct reading order.

Alt text

A text description conveying important meaning from a nontext image. Example: Alt text should explain what a graph shows.

Screen reader

Software that presents content through speech or other accessible outputs. Example: A screen reader may misread an untagged table.

Form accessibility

Designing interactive fields with understandable labels and navigation. Example: A form field needs more than visual proximity to its question.

Language tag

Metadata indicating the language of a document or selected content. Example: Correct language tags support pronunciation by assistive tools.

Accessibility Checker

A tool identifying selected issues that may affect PDF accessibility. Example: A checker cannot certify the complete user experience.

Table header

A label identifying the purpose of rows or columns in a table. Example: A complex table needs meaningful headers.

Document title

A descriptive name exposed by document metadata or interface rather than only filename. Example: Use a real title for an accessible report.

Hyperlink

An interactive reference to a URL, document destination or other eligible action. Example: Use link text describing the destination.

Bookmark navigation

Using PDF bookmarks to move through sections of a long report. Example: Bookmarks help readers reach appendices.

Find text

Search for words in a PDF’s machine-readable text layer. Example: A scanned image may require OCR before Find works.

Copy text

Extract selected content to the clipboard under permitted settings. Example: Copied OCR text may contain recognition mistakes.

Export to Word

Convert supported PDF material into a Word document, subject to format limitations. Example: A converted Word table should be reviewed for layout errors.

Export to Excel

Convert eligible PDF tables or structures into a spreadsheet. Example: Check extracted numbers and formulas independently.

Print to PDF

Create a PDF by using a supported operating-system print process rather than editing the original source. Example: Printing to PDF may flatten interactive form elements.

Page layout

The arrangement of content, margins and page dimensions. Example: Check layout before signing or printing.

PDF protection, redaction and responsible sharing

The following 36 terms belong to one PDF workflow. Each one includes a realistic example to show why the distinction matters.

Open password

A credential required to access an encrypted PDF under selected document-security settings. Example: An open password should not be sent in the same public link.

Permissions password

A credential controlling authorised changes to a protected PDF’s print, edit or copy settings. Example: A permissions password is not the same as the document-opening password.

Password protection

Applying selected access or permissions restrictions to a document. Example: Password protection depends on encryption and secure handling.

Encrypt PDF

Use cryptographic protection under eligible Acrobat security settings. Example: Encryption does not guarantee the recipient’s device is secure.

Restrict printing

A permission control limiting printing under compliant reader behaviour. Example: A print restriction does not make screenshots impossible.

Restrict copying

A PDF permission limiting selected copy functions under compatible applications. Example: A restriction can be bypassed by external capture methods.

Restrict editing

A permission setting limiting authorised alterations in suitable PDF tools. Example: Check the document’s restriction summary before editing.

Redaction

Permanent removal of selected visible text or images using a proper PDF redaction workflow. Example: A drawn black rectangle is not secure redaction.

Mark for redaction

Identify text or graphics that should be removed when redactions are applied. Example: Review every marked occurrence before applying.

Apply redactions

Execute irreversible removal of selected marked content and save the redacted PDF. Example: Keep a protected original before applying redactions.

Redaction box

A visible replacement area covering content removed by a secure redaction operation. Example: A black box can be safe only if the underlying content was truly removed.

Black highlight

A decorative or annotation mark that may leave original text accessible beneath it. Example: Never use a black highlight alone for confidential removal.

Sanitization

Removing selected hidden or nonvisible PDF information, including metadata and other sensitive elements. Example: Sanitize after redacting visible private information.

Hidden metadata

Information embedded in the file that may reveal names, systems or activity. Example: Metadata can expose details not visible on a printed page.

Embedded attachment

A separate file packaged inside a PDF that may need independent review. Example: Check embedded attachments before sharing legal records.

JavaScript in PDF

Document-based scripting supported by some PDF applications and workflows. Example: Be cautious with unexpected PDFs requesting unusual actions.

Digital certificate

A cryptographic credential associated with signatures or encryption. Example: Certificate properties require validation.

Watermark

A visible or embedded mark identifying a draft, ownership claim or status. Example: A Draft watermark does not technically protect information.

Confidential label

A classification indicating limited intended distribution, without necessarily enforcing access control. Example: A Confidential label is not encryption.

Flatten PDF

Convert selected interactive elements or layers into a less editable representation under applicable tools. Example: Flattening is not guaranteed redaction or sanitization.

PDF permissions summary

A document-property overview of whether printing, editing and copying are permitted. Example: Inspect the permissions summary before changing the file.

Protected mode

An application security feature intended to reduce risks when opening untrusted documents. Example: Protected mode does not replace a trusted source check.

Malicious PDF

A document crafted to exploit software or deceive users. Example: Do not open unexpected attachments on outdated software.

Phishing attachment

A file used as part of a deceptive request for login details, money or unsafe actions. Example: An invoice PDF can contain a fraudulent payment link.

Untrusted link

A destination whose identity is not verified, even when embedded in a formal-looking document. Example: Open bank sites independently rather than from surprise PDFs.

Digital forgery

An unauthorised alteration intended to misrepresent a document’s content or origin. Example: A realistic seal image does not prove a document is genuine.

Source file

The original editable Word, spreadsheet or design document before PDF conversion. Example: Keep the source file for genuine revisions.

Approved version

The document a responsible person has reviewed and authorised for release. Example: Approved and latest modified are not synonymous.

Version history

A record of revisions maintained through a storage or collaboration system. Example: Keep older versions securely when policies require.

Retention rule

A policy or legal obligation defining how long a record should be kept. Example: Deleting a signed PDF may violate a retention requirement.

Secure sharing

Distributing a file only to authorised people through appropriate protections. Example: Check file permissions in the sharing service, not only the PDF.

External recipient

A person or account outside the originating organisation. Example: Confirm the recipient’s identity before sending client records.

Least privilege

Giving someone only the access necessary for their work. Example: A reviewer may need comment rather than edit rights.

Audit trail

A record of important actions or signature events under an authorised process. Example: An audit trail can support accountability but is not proof every claim is true.

Recovery copy

A separate preserved version kept so important source material can be restored if needed. Example: Keep a recovery copy before permanent redaction.

Irreversibility

The inability to restore content after a genuine destructive operation without a separate copy. Example: Applied redactions cannot simply be undone later from the same saved file.

Five real Acrobat situations and what to do

A scanned PDF cannot be searched

A scanned page may contain only a photographic image. Use an eligible OCR or Recognize Text workflow to create a searchable layer, selecting the right document language and scan quality. Adobe’s current scan help explains OCR options and image-quality adjustments. After recognition, search for an exact number or name and compare it with the visible source. A wrong OCR result could cause an incorrect contract review.

Someone says they cannot type into a form

A PDF may be a noninteractive flat form rather than one with actual fillable fields. Acrobat’s Fill & Sign tools can place typed text and checkmarks on supported PDFs. An interactive form may have highlighted fields, keyboard navigation and validation. Check the document’s protection settings if controls are disabled. Do not use someone else’s signature or invent information to bypass a required field.

A manager wants three signatures in a defined order

Adobe’s Request e-signatures feature supports eligible recipient assignments, required fields, signing orders and agreement tracking. Sending the file is not the same as collecting signed acceptance. Confirm all intended signers and email addresses, inspect the final agreement status and preserve the signed copy with the applicable audit information. Some organisations may require a certificate-based digital signature rather than an ordinary e-signature workflow.

A PDF must be sent without personal identity numbers

Use Acrobat Pro’s redaction tools to identify and remove the visible data; then review hidden information through sanitization. Adobe’s October 2026 help explains that redaction does not automatically erase every hidden item unless additional removal is applied. Inspect the finished file, test search for the redacted number, and retain the original in a properly restricted location for authorised records.

A shared PDF cannot be copied or printed

The document may have a permissions password controlling editing, printing or copying. Adobe documents how to inspect Document Properties and the restriction summary. Respect the creator’s rights and do not try to bypass controls. Permission restrictions are not a guarantee that an authorised reader cannot photograph the screen or retype what they see.

Six PDF mistakes people make

Flattening versus redaction: removing interactivity does not guarantee that sensitive underlying data has been securely removed.
Black rectangle versus redact: a visible cover is not the same as permanent content removal.
Redaction versus sanitization: visible content and hidden data require separate checks.
Image-only scan versus searchable PDF: OCR adds text information that can still contain recognition errors.
Electronic versus digital signatures: a general signing action differs from certificate-based cryptographic validation.
Signed versus valid: a visible signature is not proof the signer had authority or that legal requirements are met.
Compress versus improve: smaller files may lose image detail.
PDF/A versus guaranteed preservation: an archival standard helps with format suitability but does not replace backup or retention planning.
Permissions password versus document-open password: modification restrictions differ from access restrictions.
Review comment versus final edit: a sticky note does not change the original contractual wording.

A safe Acrobat document workflow

1. Identify the source. Confirm the sender, document type, number of pages and whether the file is an image scan, searchable text or a signed document. Be cautious with unexpected embedded links and attachments.

2. Decide the outcome. Are you filling a form, editing prose, combining files, seeking signatures, redacting data or preparing an archival copy? Different operations carry different risks.

3. Preserve an appropriate original. Before OCR corrections, page deletion, flattening or permanent redaction, keep an authorised original so mistakes can be investigated without exposing it to unnecessary recipients.

4. Apply the right tool. Fill & Sign for ordinary form completion; Request e-signatures for the designated signing workflow; certificate tools for digital signatures; Redact and Sanitize for sensitive data.

5. Inspect the actual output. Open the newly saved file, verify page order, signatures, visible and hidden information, accessibility and the destination recipients’ permissions.

6. Keep the audit record. For consequential agreements or official submissions, retain the correct signed version and supporting evidence under the applicable retention policy.

Practice your PDF vocabulary

A photo of an agreement must become searchable: OCR.
A PDF has fields for name, date and choice: interactive form.
A user adds typed text over a scanned form: Fill & Sign.
A manager needs recipients to sign in sequence: Request e-signatures and signing order.
A signer uses a certificate and digital ID: digital signature.
Private text must disappear from the underlying file: proper redaction.
Invisible author names or hidden layers must be removed: sanitization.
A password controls who can open a PDF: document-open password.
A password restricts editing or copying: permissions password.
A report is prepared for a long-term archival standard: appropriate PDF/A conformance.

Frequently asked questions

What is OCR in Adobe Acrobat?

Optical character recognition converts scanned images of words into machine-readable text so they can be searched and sometimes edited. Results need verification.

Is adding a black rectangle a safe way to redact text?

No. A drawn shape can leave underlying information in the file. Use a proper redaction and sanitization workflow.

What is the difference between electronic and digital signatures?

Electronic signature is a broader concept. Certificate-based digital signatures use cryptographic credentials and integrity validation, subject to their trust and legal context.

Does Fill & Sign make a form legally binding?

Not by itself. The significance of a signature depends on the transaction, parties, applicable law and any receiving institution’s requirements.

What does a permissions password protect?

It restricts selected operations such as editing, printing or copying in compatible PDF software. It is different from an opening password.

Does compression always preserve PDF quality?

No. Compression may reduce size by altering images or other resources. Check readability after export.

Can redacted material be restored after applying redactions?

Adobe says applied and saved redactions are permanent in the resulting file. Keep a separate authorised original when required.

Does PDF/A replace backups?

No. PDF/A is a format and conformance family intended for long-term preservation; storage, backups, access and retention are separate concerns.

Vocabulary for Adobe Acrobat | PDF Forms, Signatures and Redaction Explained