Tape measures allow you to find the dimensions (length, width, height and depth) of a particular space or item. They can be divided into two main categories: self-retracting tapes and reel tapes. Self-retracting tapes are intended for smaller spaces: individual rooms, pieces of furniture, windows and doors. These tapes range from 10' to 30' in length, and may be locked in an extended position or automatically retracted. Tape reels, on the other hand, are intended to measure very large spaces. Their tapes may be up to 300' long and frequently need to be manually retracted by turning a reel.