What is the main purpose of a dive computer?

The primary function of a dive computer is to monitor depth, time, and nitrogen levels during a dive. This real-time data is crucial for ensuring diver safety, as it helps prevent decompression sickness by tracking the cumulative nitrogen levels absorbed by the diver's body. The dive computer continuously updates this information throughout the dive, allowing divers to make informed decisions about their ascent rate and safety stops based on their current depth and time spent underwater.

While calculating dive tables is important for planning dives, this task is typically performed before the dive and does not serve as the main purpose of a dive computer. Similarly, documenting diving history can be relevant for certifications, but it is not the core function of a dive computer. Recording underwater photos is outside the scope of what a dive computer is designed for, as its primary role is to enhance safety and provide critical information during the dive itself.