Umm, OSX storage problems :/ suggestions please...

Xl5saoh_medium

Why is my "Other" section so large. I do back up with time machine but because I'm on a desktop mac, local snapshots aren't created so that's not what's causing this massive amount of space. any free applications out there that can help me determine what file types are causing this other section to become unusually large?

PS. i know i have 4TB of storage, but that 150+GB of space is worrying me,