---
title: "Glossary: PDF, OCR, Excel and AI terms – Docsi AI"
description: "104 terms about PDF, text recognition, Excel, CSV, sources, AI and subscriptions, explained briefly – each linked to the matching Docsi AI guide."
url: https://docsi.impulse-apps.de/en/glossary/
language: en
website: Docsi
publisher: Impulse Apps
---

[← Guides](https://docsi.impulse-apps.de/en/guides/)

# Glossary: 104 terms about documents and AI

From Archived copy to XLSX: 104 terms from the Docsi AI guides, explained briefly and clearly. Every entry links to the guide that puts the term in context.

- A
- B
- C
- D
- E
- F
- G
- H
- I
- K
- L
- M
- N
- O
- P
- R
- S
- T
- U
- V
- W
- X

## A

- **Archived copy**: A saved version of a web page at a specific point in time, for example in the Wayback Machine. [→ Web pages as sources](https://docsi.impulse-apps.de/en/guides/use-a-web-page-as-text-source/#glossary)

## B

- **Backup**: An additional copy in another place, for example via Time Machine or Windows Backup. [→ Local drafts](https://docsi.impulse-apps.de/en/guides/local-drafts-and-retention/#glossary)
- **Balance**: The credits still available to you in the current billing period. [→ Credits and devices](https://docsi.impulse-apps.de/en/guides/credits-and-devices/#glossary)
- **Bar chart**: Compares values through the length of bars; the axis should start at zero. [→ Charts](https://docsi.impulse-apps.de/en/guides/charts-with-a-clear-message/#glossary)
- **Base**: The total a percentage refers to. [→ Analysing spreadsheets](https://docsi.impulse-apps.de/en/guides/analyse-spreadsheets/#glossary)
- **Billing period**: The month Stripe bills your subscription for and for which your allowance applies. [→ Credits and devices](https://docsi.impulse-apps.de/en/guides/credits-and-devices/#glossary)
- **Bookmarks**: The outline of a PDF in the sidebar. Docsi exports create them from the headings. [→ Merging PDFs](https://docsi.impulse-apps.de/en/guides/merge-pdfs/#glossary)

## C

- **Character encoding**: The rule for storing characters as bytes, such as UTF-8. [→ Checking CSV data](https://docsi.impulse-apps.de/en/guides/check-csv-data/#glossary)
- **Checksum**: A fingerprint of a file (SHA-256 in Docsi). If the file changes, the checksum changes. [→ Reviewing sources](https://docsi.impulse-apps.de/en/guides/review-sources/#glossary)
- **Citation style**: A set format for references, such as APA or Harvard. Docsi provides file and page; you add author and year. [→ Reviewing sources](https://docsi.impulse-apps.de/en/guides/review-sources/#glossary)
- **Context**: All content an AI task sees: the message, earlier steps, source excerpts and remembered details. [→ AI and privacy](https://docsi.impulse-apps.de/en/guides/ai-and-privacy/#glossary)
- **Contrast**: The brightness difference between text and background; high contrast improves recognition. [→ Text from images](https://docsi.impulse-apps.de/en/guides/review-text-from-images/#glossary)
- **Conversation**: A connected sequence of requests. Docsi considers up to 16 earlier steps in it, but no other conversations. [→ Getting started](https://docsi.impulse-apps.de/en/guides/getting-started/#glossary)
- **Credit**: The unit of usage for the built-in Docsi AI. Local tools use no credits. [→ Getting started](https://docsi.impulse-apps.de/en/guides/getting-started/#glossary)
- **Cropping**: Removing unnecessary image margins so the relevant text stays larger. [→ Text from images](https://docsi.impulse-apps.de/en/guides/review-text-from-images/#glossary)
- **CSV**: A text file holding one sheet, with fields separated by comma, semicolon or tab. [→ Converting files](https://docsi.impulse-apps.de/en/guides/convert-files/#glossary)

## D

- **Data minimisation**: A GDPR principle: process only as much personal data as necessary. [→ AI and privacy](https://docsi.impulse-apps.de/en/guides/ai-and-privacy/#glossary)
- **Data series**: A sequence of related values, such as one year’s revenue per month. [→ Charts](https://docsi.impulse-apps.de/en/guides/charts-with-a-clear-message/#glossary)
- **Date accessed**: The date you read a web page; important for pages that change. [→ Web pages as sources](https://docsi.impulse-apps.de/en/guides/use-a-web-page-as-text-source/#glossary)
- **Deadline**: The date by which a task should be completed. [→ Meeting notes](https://docsi.impulse-apps.de/en/guides/organise-meeting-notes/#glossary)
- **Decision**: An explicit agreement of the group, recorded in the minutes. [→ Meeting notes](https://docsi.impulse-apps.de/en/guides/organise-meeting-notes/#glossary)
- **Delimiter**: The character between the fields of a CSV line: comma, semicolon or tab. [→ Checking CSV data](https://docsi.impulse-apps.de/en/guides/check-csv-data/#glossary)
- **Dependency**: A passage that relies on another, such as a definition later sections refer to. [→ Comparing versions](https://docsi.impulse-apps.de/en/guides/compare-document-versions/#glossary)
- **Device seat**: An activated computer. Plus has 2 seats, Pro 3. [→ Credits and devices](https://docsi.impulse-apps.de/en/guides/credits-and-devices/#glossary)
- **Digital signature**: A cryptographic proof for an unchanged file. It does not apply to a newly merged PDF. [→ Merging PDFs](https://docsi.impulse-apps.de/en/guides/merge-pdfs/#glossary)
- **Direct quote**: A sentence taken over unchanged in quotation marks, with a page number in the citation style. [→ Reviewing sources](https://docsi.impulse-apps.de/en/guides/review-sources/#glossary)
- **Docsi AI**: The built-in AI based on the GLM language model by Z.ai, reached through the Docsi server. [→ AI and privacy](https://docsi.impulse-apps.de/en/guides/ai-and-privacy/#glossary)
- **DOCX**: The Word format following the open Office Open XML standard (ECMA-376). [→ Converting files](https://docsi.impulse-apps.de/en/guides/convert-files/#glossary)
- **Donut chart**: Shows parts of a whole as a ring; suitable only for a few categories. [→ Charts](https://docsi.impulse-apps.de/en/guides/charts-with-a-clear-message/#glossary)
- **dpi**: Dots per inch, a measure of scan resolution. Around 300 dpi is a good guide for normal text. [→ Text recognition](https://docsi.impulse-apps.de/en/guides/text-recognition/#glossary)
- **Draft**: An intermediate state of a result in the app’s local working store. [→ Local drafts](https://docsi.impulse-apps.de/en/guides/local-drafts-and-retention/#glossary)

## E

- **Embedded font**: A typeface contained in the file so the document looks the same everywhere. [→ Export formats](https://docsi.impulse-apps.de/en/guides/export-formats/#glossary)
- **Evidence**: The passage in a source that a statement relies on. [→ Reviewing sources](https://docsi.impulse-apps.de/en/guides/review-sources/#glossary)
- **Export**: A file you saved in PDF, Word, Excel, CSV or Markdown format. [→ Local drafts](https://docsi.impulse-apps.de/en/guides/local-drafts-and-retention/#glossary)

## F

- **Field**: A single value in a CSV line, equivalent to a cell. [→ Checking CSV data](https://docsi.impulse-apps.de/en/guides/check-csv-data/#glossary)
- **File signature**: The first bytes of a file, which reveal its actual type regardless of the extension. [→ Protected files](https://docsi.impulse-apps.de/en/guides/protected-files-and-import-errors/#glossary)
- **Flashcard**: A pair of question or term and answer. Docsi lays cards out in pairs in the PDF and delivers them as a table on request. [→ Study sheets](https://docsi.impulse-apps.de/en/guides/create-study-sheets/#glossary)
- **Formula cell**: A cell containing a formula. Docsi does not count it by default because its stored result may be outdated. [→ Analysing spreadsheets](https://docsi.impulse-apps.de/en/guides/analyse-spreadsheets/#glossary)

## G

- **Grouping**: Combining rows by a feature, such as the sum per region. [→ Analysing spreadsheets](https://docsi.impulse-apps.de/en/guides/analyse-spreadsheets/#glossary)

## H

- **Header row**: The first line of a CSV file with the column names. [→ Checking CSV data](https://docsi.impulse-apps.de/en/guides/check-csv-data/#glossary)
- **HEIC**: The default photo format of many iPhones; convert to JPEG before adding. [→ Text from images](https://docsi.impulse-apps.de/en/guides/review-text-from-images/#glossary)

## I

- **Interruption**: A task ends before the result is complete, for example due to a lost connection or cancelling. [→ Interrupted tasks](https://docsi.impulse-apps.de/en/guides/resume-interrupted-tasks/#glossary)
- **ISO 4217 code**: The three-letter currency code, such as EUR, USD or CHF. [→ Receipts into tables](https://docsi.impulse-apps.de/en/guides/turn-receipts-into-tables/#glossary)
- **ISO date**: A date in year-month-day format, such as 2026-10-29, unambiguous in every language. [→ Checking CSV data](https://docsi.impulse-apps.de/en/guides/check-csv-data/#glossary)

## K

- **Keychain**: The operating system’s protected credential store, where Docsi keeps keys. [→ AI and privacy](https://docsi.impulse-apps.de/en/guides/ai-and-privacy/#glossary)

## L

- **License key**: The key in the format DOCSI-XXXXX-XXXXX-XXXXX-XXXXX that links a device to your subscription. [→ Credits and devices](https://docsi.impulse-apps.de/en/guides/credits-and-devices/#glossary)
- **Line chart**: Shows a trend along an ordered axis, usually time. [→ Charts](https://docsi.impulse-apps.de/en/guides/charts-with-a-clear-message/#glossary)
- **Local model**: A language model running on your computer, for example through Ollama or LM Studio. [→ AI and privacy](https://docsi.impulse-apps.de/en/guides/ai-and-privacy/#glossary)
- **Local model server**: A program such as Ollama or LM Studio that serves a language model on your computer. [→ Interrupted tasks](https://docsi.impulse-apps.de/en/guides/resume-interrupted-tasks/#glossary)
- **LSTM**: The neural recognition method of Tesseract that Docsi uses exclusively. [→ Text recognition](https://docsi.impulse-apps.de/en/guides/text-recognition/#glossary)

## M

- **Macro**: A program embedded in Office files. Docsi rejects files with macros. [→ Protected files](https://docsi.impulse-apps.de/en/guides/protected-files-and-import-errors/#glossary)
- **Markdown**: Plain readable text with characters for headings, lists and tables, such as “#” and “|”. [→ Converting files](https://docsi.impulse-apps.de/en/guides/convert-files/#glossary)
- **Mean**: The sum of all values divided by their count. Sensitive to outliers. [→ Analysing spreadsheets](https://docsi.impulse-apps.de/en/guides/analyse-spreadsheets/#glossary)
- **Median**: The middle value of a sorted series. Robust against outliers. [→ Analysing spreadsheets](https://docsi.impulse-apps.de/en/guides/analyse-spreadsheets/#glossary)
- **Merging**: Copying the pages of several PDFs unchanged one after another into a new file. [→ Merging PDFs](https://docsi.impulse-apps.de/en/guides/merge-pdfs/#glossary)
- **Metadata**: Information about a file such as title, language and date that is not part of the visible text. [→ Export formats](https://docsi.impulse-apps.de/en/guides/export-formats/#glossary)
- **Modal word**: Words such as “must”, “should” or “may” that set the degree of an obligation. [→ Comparing versions](https://docsi.impulse-apps.de/en/guides/compare-document-versions/#glossary)

## N

- **Native charts**: Charts that Word or Excel recognise as their own objects and can edit. [→ Export formats](https://docsi.impulse-apps.de/en/guides/export-formats/#glossary)
- **Net and gross**: Net is the amount without VAT, gross the amount including VAT. [→ Receipts into tables](https://docsi.impulse-apps.de/en/guides/turn-receipts-into-tables/#glossary)

## O

- **OCR**: Optical character recognition: recognising text in images and scanned pages. [→ Text recognition](https://docsi.impulse-apps.de/en/guides/text-recognition/#glossary)
- **Open password**: Encrypts a file; without the password it cannot be read. [→ Protected files](https://docsi.impulse-apps.de/en/guides/protected-files-and-import-errors/#glossary)
- **Original**: The original file, which Docsi only reads and never changes. [→ Local drafts](https://docsi.impulse-apps.de/en/guides/local-drafts-and-retention/#glossary)
- **Owner**: The person who completes a task or makes sure it gets done. [→ Meeting notes](https://docsi.impulse-apps.de/en/guides/organise-meeting-notes/#glossary)

## P

- **Paraphrase**: A statement from the source in your own words. It also needs a source reference. [→ Reviewing sources](https://docsi.impulse-apps.de/en/guides/review-sources/#glossary)
- **Partial draft**: An incomplete result that can be reused as a working state. [→ Interrupted tasks](https://docsi.impulse-apps.de/en/guides/resume-interrupted-tasks/#glossary)
- **PDF/A**: A standardised PDF variant for long-term archiving under ISO 19005. [→ Merging PDFs](https://docsi.impulse-apps.de/en/guides/merge-pdfs/#glossary)
- **PDF/UA**: A standard for accessible PDFs. Docsi does not claim PDF/UA conformance. [→ Export formats](https://docsi.impulse-apps.de/en/guides/export-formats/#glossary)
- **Permissions password**: Allows a PDF to be opened but restricts printing, copying or editing. [→ Protected files](https://docsi.impulse-apps.de/en/guides/protected-files-and-import-errors/#glossary)
- **Proration**: On a plan change, Stripe charges only the difference for the remaining days. [→ Credits and devices](https://docsi.impulse-apps.de/en/guides/credits-and-devices/#glossary)

## R

- **Reader view**: A browser view that shows only the article text and hides ads. [→ Web pages as sources](https://docsi.impulse-apps.de/en/guides/use-a-web-page-as-text-source/#glossary)
- **Receipt**: Proof of a business transaction, such as an invoice, receipt or till slip. [→ Receipts into tables](https://docsi.impulse-apps.de/en/guides/turn-receipts-into-tables/#glossary)
- **Recognition confidence**: An engine estimate between 0 and 100. It is not a probability that the text is correct. [→ Text recognition](https://docsi.impulse-apps.de/en/guides/text-recognition/#glossary)
- **Recorded changes**: A Word feature that records changes visibly until they are accepted or rejected. [→ Comparing versions](https://docsi.impulse-apps.de/en/guides/compare-document-versions/#glossary)
- **Retrieval practice**: Learning by actively recalling, for example with review questions or flashcards, instead of re-reading. [→ Study sheets](https://docsi.impulse-apps.de/en/guides/create-study-sheets/#glossary)
- **Review question**: A question that checks whether you understood a section, ideally with an answer and page reference. [→ Study sheets](https://docsi.impulse-apps.de/en/guides/create-study-sheets/#glossary)

## S

- **Screen recording permission**: The macOS permission an app needs to capture other windows. [→ Windows as sources](https://docsi.impulse-apps.de/en/guides/windows-as-sources/#glossary)
- **ScreenCaptureKit**: Apple’s interface for screen and window captures on macOS. [→ Windows as sources](https://docsi.impulse-apps.de/en/guides/windows-as-sources/#glossary)
- **Screenshot**: An image of the screen content or part of it. [→ Text from images](https://docsi.impulse-apps.de/en/guides/review-text-from-images/#glossary)
- **Small invoice**: An invoice up to 250 euros, for which simplified required details apply. [→ Receipts into tables](https://docsi.impulse-apps.de/en/guides/turn-receipts-into-tables/#glossary)
- **Source**: A file, window or pasted text Docsi reads for a task. Sources are numbered (Q1, Q2 …). [→ Getting started](https://docsi.impulse-apps.de/en/guides/getting-started/#glossary)
- **Source marker**: A reference in the result to a passage of a source, with the page number for PDFs. Docsi checks every marker against the original. [→ Getting started](https://docsi.impulse-apps.de/en/guides/getting-started/#glossary)
- **Spaced repetition**: Reviewing at intervals over several days instead of in one long block. [→ Study sheets](https://docsi.impulse-apps.de/en/guides/create-study-sheets/#glossary)
- **Statement title**: A chart title that states the key message instead of just the topic. [→ Charts](https://docsi.impulse-apps.de/en/guides/charts-with-a-clear-message/#glossary)
- **Status code 429**: The HTTP response “Too Many Requests”: a service is not accepting further requests right now. [→ Interrupted tasks](https://docsi.impulse-apps.de/en/guides/resume-interrupted-tasks/#glossary)
- **Storage limitation**: GDPR principle: keep personal data only as long as the purpose requires. [→ Local drafts](https://docsi.impulse-apps.de/en/guides/local-drafts-and-retention/#glossary)
- **Study sheet**: A short, structured summary of a topic with key terms, takeaways and questions for practice. [→ Study sheets](https://docsi.impulse-apps.de/en/guides/create-study-sheets/#glossary)
- **Summarising**: Shortening the content with AI. That is a different workflow from merging. [→ Merging PDFs](https://docsi.impulse-apps.de/en/guides/merge-pdfs/#glossary)

## T

- **Task**: A concrete action with an owner and a date, often called an action item. [→ Meeting notes](https://docsi.impulse-apps.de/en/guides/organise-meeting-notes/#glossary)
- **Technical diff**: A list of all text differences between two files, for example with “Compare” in Word. [→ Comparing versions](https://docsi.impulse-apps.de/en/guides/compare-document-versions/#glossary)
- **Text layer**: The invisible, selectable text of a PDF. If it is missing, the page consists only of an image. [→ Text recognition](https://docsi.impulse-apps.de/en/guides/text-recognition/#glossary) · The selectable text of a PDF; a PDF saved from the browser usually has one. [→ Web pages as sources](https://docsi.impulse-apps.de/en/guides/use-a-web-page-as-text-source/#glossary)
- **Timeout**: A service does not respond within the expected time; the connection is closed. [→ Interrupted tasks](https://docsi.impulse-apps.de/en/guides/resume-interrupted-tasks/#glossary)
- **Transcript**: A verbatim written version of what was said. Docsi does not create transcripts but can work with existing ones. [→ Meeting notes](https://docsi.impulse-apps.de/en/guides/organise-meeting-notes/#glossary)
- **Typesetting**: Arranging text, tables and figures on pages. Docsi sets PDFs with its own layout engine. [→ Export formats](https://docsi.impulse-apps.de/en/guides/export-formats/#glossary)

## U

- **URL**: The address of a web page, such as example.com/article. [→ Web pages as sources](https://docsi.impulse-apps.de/en/guides/use-a-web-page-as-text-source/#glossary)
- **UTF-8**: The most widespread character encoding, covering accented letters and all Unicode characters. [→ Converting files](https://docsi.impulse-apps.de/en/guides/convert-files/#glossary)

## V

- **VAT**: The tax on goods and services, in Germany 19 percent standard and 7 percent reduced. [→ Receipts into tables](https://docsi.impulse-apps.de/en/guides/turn-receipts-into-tables/#glossary)
- **Version**: A particular state of a document, ideally named with date and role. [→ Comparing versions](https://docsi.impulse-apps.de/en/guides/compare-document-versions/#glossary)
- **Visible area**: The part of a window currently shown on screen. Only this part is captured. [→ Windows as sources](https://docsi.impulse-apps.de/en/guides/windows-as-sources/#glossary)
- **Vision model**: An AI model that can process images as well as text. [→ Text from images](https://docsi.impulse-apps.de/en/guides/review-text-from-images/#glossary)

## W

- **Widget**: The slim Docsi bar at the top of the screen. It opens when you hover over it and accepts files, windows and quick questions. [→ Getting started](https://docsi.impulse-apps.de/en/guides/getting-started/#glossary)
- **Window drop**: Dragging a window onto Docsi so he takes an image of it and reads the text. [→ Windows as sources](https://docsi.impulse-apps.de/en/guides/windows-as-sources/#glossary)
- **Windows.Graphics.Capture**: The public Windows interface for screen and window captures. [→ Windows as sources](https://docsi.impulse-apps.de/en/guides/windows-as-sources/#glossary)
- **Working copy**: A separate copy for further work, so the original stays unchanged. [→ Protected files](https://docsi.impulse-apps.de/en/guides/protected-files-and-import-errors/#glossary)

## X

- **XLSX**: The Excel format under Office Open XML with several sheets and typed cells. [→ Converting files](https://docsi.impulse-apps.de/en/guides/convert-files/#glossary)

## How this glossary was made

The explanations come from the “Key terms explained” sections of the [Docsi AI guides](https://docsi.impulse-apps.de/en/guides/). They describe the terms as they come up when you work with Docsi and do not replace a technical definition. The primary sources for formats, standards and methods are listed at the end of each guide.