Variables

Here's an empty trinket...

Type in the following, Run it, and see what happens.

a = 1
b = 2
print(a + b)

What output did you get? Was it a 3? Congratulations! You have just done algebra (...or at least you had Python do it for you...)!

Let's look at what you just did...

a = 1   # This creates a variable named "a" and gave it the value of 1
b = 2   # This creates another variable named "b" and gave it the value of 2
print(a + b)  # Finally, we tell Python to add "a" and "b", then print the result

Variables stores values. This can be a number or a string. When we give a variable a value, Python will remember it for us. We can then use the variable in place of the value.

Here's another empty trinket...

Type in the following, Run it, and see what happens.

print("Hi there!")
a = "Hi there!"
print(a)

In the above program, both of the print lines do the same thing. In the first print, we told Python to output "Hi there!", while in the second print we first store the value of "Hi there!" in a variable a then tell Python to output the value of a.

We can do math with variables as well! Try the following

a = 2
b = 3
c = a + b
print(c)

a = 5
b = a * 2
print(b)

We can also use variables with strings!

a = "Hello"
b = "World"
print(a + b)

Now that probably didn't come out right. Can you add a space in between "Hello" and "World"?