What you’re talking about (I think) are called docstrings (Thanks Boud for the link).
def foo():
"""This function does absolutely nothing"""
Now, if you type help(foo) from the interpreter, you’ll get to see the string that I put in the function. You can also access that string by foo.__doc__
Of course, string literals are just that — literal strings.
a = "This is a string literal" #the string on the right side is a string literal, "a" is a string variable.
or
foo("I'm passing this string literal to a function")
They can be defined in a bunch of ways:
'single quotes'
"double quotes"
""" triple-double quotes """ #This can contain line breaks!
or even
#This can contain line breaks too! See?
''' triple-single
quotes '''