 Haj, sreči, v tvoj videu, zelo srečimo o boljstvenih fungšnjih app. The app's function returns the absolute value of a number, or on the other words, this function returns number without its sign. For example, absolute value of minus 5 is 5. Absolute number of minus 5 is 5, and also absolute value of 5 is also 5. We could use function apps by simply call apps and put inside it number as argument. For example, let's say x equals absolute value of minus 5. If we print that x will be number 5. Similarly, if we say x equals absolute value of 5 and print x, we will get again number 5. Argument inside function apps can be positive or negative number, but we could also put an ordinary arithmetic operation as an argument. For example, let's make call of apps function with some simply arithmetic inside it. For example, 2 minus 3.4, and we will get solution 1.4. Of course, we can put also as an argument some variable. For example, y equals 3, x equals absolute value of y. In practice, of course, we don't want to use numbers as arguments in order to get absolute value. Often, we will use inside absolute function argument that is variable. For example, we could write a little program as example of how you could practically use function apps. For example, if we have ball on the position minus 2 and we have player on the position 3. How to calculate distance between ball and player? We could calculate it by summing absolute values of ball position and absolute value of player position. So distance equals absolute value of ball position plus absolute value of player position. Let's print distance. So distance between player and ball is equals 5. Thanks for watching and happy coding.