Selgitage, mis on muutujad, mille väärtust saab programmi käivitamise ajal muuta

In PHP, variables are named containers for storing data, whose values can be changed during program execution. This means you can assign a value to a variable and then change that value to another during the script's runtime.

Example:

$counter = 1; // variable with initial value 1
$counter = $counter + 1; // now the value of the variable is 2

This capability allows for dynamic data management, such as counting iterations, storing calculation results, etc.