The Linux Documentation Project is the entry point
A HOWTO document explains in detail how to do something. Related to
Linux-world, The Linux Documentation Project is the house of the HOWTOs and the mini HOWTOs.
LDP is a loosely knit team of volunteers who provide documentation for many aspects of Linux.
There are several forms of documentation available at LDP: Guides, HOWTOs, man pages, and FAQs.
“From setting up a specialized piece of hardware to tweaking your distro, from performing a system
administration task to shake a Broadcom driver, from setting up specific networking to implement software in the right way.”
The Linux Documentation Project is also the house of manuals.
A man (Manual) page is a standard form of help that is available for many Linux applications and utilities.
Many of the GNU utilities have a more detailed form of help, called info pages.
man who info who