[BLANK AUDIO]. We are going to start learning to execute code with the most basic statements in C and build up to more complex statements from there. Here we have two variable declarations, one for int called x followed by one for int called y. If we execute first statement, we will create a box labeled x. The variable x is uninitialized, so we will place a question mark in the box for its value. If we execute the second statement, we will create another box labeled y which is also uninitialized. Uninitialized variables are bad, as they lead to bugs in your code which may be hard to find and fix. Now let's look at another example which initializes the variables. Here, the first statement declares an int called x. Executing it behaves exactly as before. We have made a box for x, which has an unknown value in it. However, the next line of code assigns 4 to x. Executing this line puts a 4 in the box for x. Now x is initialized and we know that it has the value 4. The next line shows the declaration and initialization combined in a single statement. Executing it both creates a box for y and puts the value 6 in that box. Of course, variables are only useful if you make use of the values that they have. Here, the code first declares x and initializes it to a 4. Let us execute that statement. Next, it declares y and initializes it to x + 2. To perform this statement, we must evaluate the expression on the right-hand side of the equal sign, x is 4, so x + 2 is 6. We create a box for y and put a 6 in it. The last statement creates a variable z and initializes it to y- x. As you might expect, you would take the value of y, which is 6 and the value of x which is 4 and subtract them to get 2. You would then create a box for z and initialize it to 2. Great, now you know how to execute code with variable declarations and assignment statements.