11 + 56 # This is a comment.  It's meant only for humans.
23 - 52 # The "#" tells Python to ignore the rest of the line.
4 * 5   # 4 times 5.
2 ** 5  # 2 to the power of 5
8 / 3   # The "/" is division.  Not "\"!
#Note: Integer division! like in elementary school.
8 % 3   # The % is the remainder operator

#what if we don't want integers?
#we need to tell python that we're dealing with 'real' numbers.
#We do this by adding a .0 to the end of a number.
8.0/3.0
#Decimals also work but they're bad form.
8./3.
#Style and readability are important!
4/0
#lets look at error messages.
#Back to slides.

#let's looks at dir and help.
dir(__builtins__)
#        All the functions etc that are built in to basic Python.
#you can also import 'modules' (which are basically groups of related functions) and apply dir on them.
dir(media)
import media
dir(media)
#help tells you about the details of a function of module.
help(abs)
help(media)
#save shell, and look at a bit of code.
#Note how we're reusing a number all over. (also makes updating hard)
#what if we could save it?