why do we need whiletrue as it leads to infinite looping

Answer 1

Sometimes you want that.

$ cat /dev/yes
y
y
y
............

When piped, it answers 'yes' to all questions until KeyboardInterrupt.

$ cat /dev/zero can use to zero a disk

...or just have an always-on monitoring loop to update a display, etc.

Answer 2

ohh yaa.. thank u Kirk

Answer 3

Like whan you play a game and it must continuesly calculating game physics , grafics...