Linux info Command and Info Pages

Learn how to use the Linux info command to read structured documentation, navigate nodes and cross-references, and choose between Info pages and man pages.

The info command is a command-line documentation reader for Linux. It displays documentation stored in the Info format, allowing you to read command and software documentation from a terminal.

Info documentation is commonly produced from Texinfo source files. Texinfo is a documentation system designed to produce Info documents and, in many projects, other documentation formats as well.

This lesson assumes that you can open a Linux terminal and enter commands with arguments. For a broader introduction to Linux commands, see Linux command-line topics.

What Is an Info Page?

An Info page is structured documentation read by the info program. Unlike a plain text file, an Info document is organized into related sections that you can explore interactively.

Info documentation is often hypertext-like. It can contain:

Nodes, which are navigable sections within an Info document.
Menus, which list related nodes or topics.
Cross-references, which link one documentation section to another related section.

A node is a section that the Info reader can display as a separate location. A cross-reference is a link from one section to another. These features make Info useful for exploring a complete command or software manual rather than reading isolated paragraphs.

Info pages can provide a more extensive explanation than a command's manual page. For example, an Info document may explain concepts, workflows, related commands, and configuration details across several linked nodes.

Basic info Command Syntax

The general syntax is:

info [topic]

The first word, info, starts the Info documentation reader. The optional topic argument identifies the documentation page to open. A topic is commonly a command name or the name of a software package.

Open Documentation for mkdir

mkdir is a Linux command used to create directories. To request its Info documentation, run:

info mkdir

Here, info launches the reader and mkdir selects the documentation topic. If the documentation is installed, the reader opens a page describing the command.

When the page opens, read the introductory text first. Look for sections describing the command's purpose, operands, options, examples, and related behavior. The page may also show menu entries or references to other nodes. Those entries lead to more detailed parts of the documentation.

Navigating Within Info

Info is designed for interactive exploration. Instead of treating documentation as one long page, follow linked sections and menus to move through related material.

Read the current node to understand the topic being described.
Look for a menu when you want to choose a related section.
Follow a cross-reference when the current section points to a deeper explanation.
Return to earlier sections when you need to compare related topics.

For example, an introductory node for a command may point to separate nodes for options, file handling, errors, or examples. Following those references lets you investigate the subject in context.

The interactive interface may display links with special formatting. The available navigation keys and prompts are shown by the Info reader, so read the on-screen help if you are unfamiliar with the interface.

Info Pages Compared with Man Pages

The man command is another Linux documentation tool. It reads man pages, which are Unix and Linux manual pages that usually provide concise command reference information.

Feature — Info pages — Man pages

Documentation format — Info format, commonly generated from Texinfo — Manual-page format organized into sections

Typical level of detail — May provide longer explanations, concepts, tutorials, and related topics — Often concise reference material focused on usage and options

Navigation and links — Uses nodes, menus, and cross-references for interactive exploration — Usually read as an individual manual page, with references to other pages where provided

Availability by command — Only available when Info documentation is installed for the command or software — Frequently available for standard commands, but availability also depends on installed documentation

Best use case — Learning a larger system or exploring connected documentation — Quickly checking syntax, options, and command behavior

Neither format is always better. Use man when you need a short reference, and use info when you need longer explanations or want to follow related documentation. The two systems complement each other.

When an Info Page Is Missing

Not every Linux command has an Info page installed or available. Documentation may not have been written in Info format, or the relevant documentation package may not be installed on your system.

A missing Info entry does not mean that the command is unavailable. It only means that the Info reader could not find documentation for that topic in the locations it checks.

Try the corresponding manual page instead:

man mkdir

This opens the manual page for mkdir. The same pattern works for another command: replace mkdir with the command name you want to investigate.

If both sources are missing and you need more information, check the documentation packages supplied by your Linux distribution. Package names and installation procedures vary, so use your distribution's normal package-management documentation.

Troubleshooting Common Documentation Problems

The requested command has no Info page

Likely cause: The command was not documented in Info format, or its documentation is not installed.

Resolution: Try the manual page with the command name after man. For example:

man mkdir

You can also look for documentation packages provided by your distribution if you need material beyond the manual page.

The manual page does not answer your question

Likely cause: The manual page may be intended as a compact reference rather than a complete explanation.

Resolution: Try the Info topic:

info mkdir

Use its menus and cross-references to explore related nodes. This is especially useful when the subject involves several concepts or commands.

Choosing the Right Documentation Tool

Start with info topic when you expect a detailed, connected software manual.
Use man topic when you want a concise reference for a command's syntax or options.
Try the other documentation source if the first one is missing or too brief.
Read linked sections and related references instead of stopping at the first short description.

The essential distinction is that info reads structured, navigable Info documentation, while man reads manual pages. Both are valuable parts of the Linux command-line help system.

Key Terms

info: A command-line program for viewing documentation in the Info format.
Info page: A structured documentation page read by the info program, often organized into linked sections.
Texinfo: A documentation system commonly used to produce Info-format documentation.
man page: A Unix or Linux manual page providing command reference documentation.
node: A navigable section within an Info document.
cross-reference: A link from one documentation section to another related section.
mkdir: A Linux command used to create directories and an example topic for the info command.

Exam-Relevant Notes

info [topic] opens an Info documentation topic.
info mkdir requests the Info documentation for mkdir.
Info pages commonly use nodes, menus, and cross-references.
Info documentation is commonly generated from Texinfo source files.
A command without an Info page may still be installed and usable.
man mkdir is an appropriate fallback when the Info entry is unavailable.
Man pages are often concise references, while Info pages may offer longer explanations and interactive navigation.