A for loop is commonly used to execute a code block a specific number of times.

for (#expression 1; #expression 2; #expression 3)
{
  # code block
}

The for loop syntax includes 3 expressions:

• The first is evaluated only one time before the first iteration.
• The second is evaluated before each iteration. If it is TRUE, the code block is executed. Otherwise, the loop terminates.
• The third is evaluated after each iteration. Note that expressions 1 and 2 have semicolons after them.

In our counting to 10 example, the syntax becomes:

for ($count = 1; $count < 11; $count++)
{
  echo "The count is: " . $count . "\n";
}

The first expression is $count = 1, this initializes the $count variable to 1.

At each iteration, the second expression ($count < 11) is evaluated. As long as this is TRUE, the code block executes.

The final expression ($count++) executes after every iteration. In this example, $count is being incremented by 1 each iteration.

After 10 iterations, the value of the $count variable is 11. This makes the second expression FALSE and the loop execution terminates.