As your desire to dive deeper and stay longer expands, you leave the realm of recreational diving and the no decompression limits that you were taught. Diving deeper and staying longer at depth moves you into decompression diving. Decompression diving requires detailed planning, preparation, equipment, and mind set and takes you into a very advanced form of diving. If you have the desire to explore wrecks, caves, or whatever that lays in deep water, getting the proper training to safely operate and return from these depths is a must. Before you can return to the surface, you must decompress.