A listing of the pages held within the Manual is stored in a system-generated database. Accessing them is as simple as man <command>, and (usually) a detailed listing of how to use a command is presented. Check out Finding Help in Linux for more information about how to use man
Help! The Manual is Missing!
On a freshly created Linux system, it is common that the Manual Pages have not yet been generated. Running the man <command> results in errors, even for essential core utilities such as ls. This can be a problem, especially on newly created systems, as it is common to issue many commands with rarely used options. It is also worth noting that sometimes the Manual can become outdated during a software update and might need to be rebuilt.
Most distributions of Linux use a scheduled job to generate the Manual – usually daily. Predictably, there is also a manual way to generate the Manual quickly and easily. Run the mandb command to update the Manual to the latest and greatest version:
Once this has been completed, a fully populated Manual awaits the curious user. Let the learning commence!