xenial
16.04 LTS		bionic
18.04 LTS		eoan
19.10		focal
20.04 LTS		Section Description
....(1) - Executable programs or shell commands
....(2) - System calls (functions provided by the kernel)
cron(3)cron(3)cron(3)cron(3)(3) - Library calls (functions within program libraries)
....(4) - Special files (usually found in /dev)
....(5) - File formats and conventions eg /etc/passwd
....(6) - Games
....(7) - Miscellaneous (including macro packages and conventions)
cron(8)cron(8)cron(8)cron(8)(8) - System administration commands (usually only for root)