The lat pulldown is a common exercise done in fitness centers with the assistance of a machine. Its purpose is to strengthen and develop the lat muscles.
The movement consists of extending the arms above, bringing a bar toward you until your hands reach shoulder height, and then releasing the bar back up in a controlled way for one repetition. The movement is called an overhead press.
https://www.youtube.com/watch?v=r1RU4wwM4lI