What is the main difference between a reel and a spool?

The primary distinction between a reel and a spool lies in their size and usability. Spools are indeed generally smaller than reels, which allows for easier storage and transport. This compact size makes spools particularly convenient for divers who need to manage their equipment effectively in restricted spaces or during dives where minimizing bulk is advantageous.

While reels can be utilized for various diving purposes, their larger size can make them less practical for situations that require a lightweight setup. Moreover, spools are often preferred for deploying guide lines or lifts in scenarios where ease of handling and storage play significant roles, such as in cave diving or when managing entanglement risks.

The other statements do touch on characteristics of diving equipment but do not capture the essential differences regarding size and storage practicality between the two, which is foundational in selecting the appropriate tool based on the dive's requirements.