Assignment operators, as the name suggests, assign (or re-assign) values to a variable. While there are quite a few variations of assignment operators, they all build off of the basic assignment operator.
The other assignment operators are a shorthand for performing some operation using the variable (indicated by x above) and value (indicated by y above) and then assigning the result to the variable itself.
For example, below is the syntax for the addition assignment operator:
x += y;
This is the same as applying the addition operator and reassigning the sum to the original variable (i.e., x), which can be expressed by the following code:
x = x + y;
To illustrate this using actual values, here is another example of using the addition assignment operator: