Where the function, to see date in terminal, is saved?

Question

I mean, there isn't any function written in ~/.bashrc which can be used for showing date.

Answer 1

You have functions and alias'es in your .bashrc or .profile implementing different features, and you have built-in functions in bash (or other shells). And some functionality are implemented as binary programs in /bin, /usr/bin or elsewhere.

You can use the command type to show where a 'program' is:

$ type date
date is /bin/date
$ type test
test is a shell builtin
$ type ls
ls is aliased to 'ls --color=auto'
$ type cd
cd is a shell builtin
$ type type
type is a shell builtin