Variables and operations

Variables are simply values that are allocated somewhere in the memory of our computer. They are similar to variables in mathematics. They can be anything: text, integers, or floats (a number with precision after the decimal point, such as 2.33).

To create a new variable, you only need to write this:

x = 2

In this case, we have named a variable x and set its value to 2.

As in mathematics, you can perform some operations on these variables. The most common operations are addition, subtraction, multiplication, and division. The way to write them in Python is like this:

x = x + 5   #x += 5
x = x - 3   #x -= 3
x = x * 2.5 #x *= 2.5
x = x / 3   #x /= 3

If you look at it for the first time, it doesn't make much sense—how can we write that x = x + 5?

In Python, and in most code, the "=" notation doesn't mean the two terms are equal. It means that we associate the new x value with the value of the old...