In almost every single Python program you write, you will have variables. Variables act as placeholders for data. They can aid in short hand, as well as with logic, as variables can change, hence their name.
Variables help programs become much more dynamic, and allow a program to always reference a value in one spot, rather than the programmer needing to repeatedly type it out, and, worse, change it if they decide to use a different definition for it.
Variables can be called just about whatever you want. You wouldn't want them to conflict with function names, and they also cannot start with a number.
You want to be careful what you name variables, classes (discussed later), and functions (discussed later), so that they do not have the same names as eachother.
For example, you have leared about the print function. What if you go and define a variable named print?
Say, for example, you do:
print = print("Uh oh!")
Now you have a variable and a function named print, which can cause trouble down the road!
exampleVar = 55 print(exampleVar)
In this case, we will have a 55 printed out to console. So, in this case, we were able to store an integer to our variable.
cannotDo = Hey!
Hey! is not a valid datatype, and this will throw an error. You would need to throw quotes around the string.
canDo = 'Hey!' print(canDo)
This is acceptable.
canContainOperations = 5/4 print(canContainOperations)
Here, we can see that we were even able to store the result of a calculation to our variable.
We can even store a variable to our variable, or an operation with our variables to a variable. Something like var3 = (var2/var1) would work. You can store other things, like functions, as well to variables. More on that later!
Try playing with variables in the console provided above, or via your own Python installation. Once you feel comfortable with them, proceed to the next tutorial.