man pages are split up into 8 sections
1 2 3 4 5 6 7 8

$ man 2 read
means “get me the man page for read from section 2”.

There’s both - a program called “read” - and a system call called “read”

So

$ man 1 read
gives you a different man page from
$ man 2 read

If you don’t specify a section, man will look through all the sections & show the first one it finds.

man page sections

1. programs
   $ man grep
$ man ls

2. system calls
   $ man sendfile $ man ptrace

3. C functions
   $man printf $ man fopen

4. devices
   $ man null for /dev/null docs

5. file formats
   $ man sudoers for /etc/sudoers
$ man proc files in /proc!

6. games
   not super useful. $man sl is my favourite from that section

7. miscellaneous
   explains concepts!
   $man 7 pipe
$ man 7 symlink

8. sysadmin programs
   $ man apt
$ man chroot