Sleeping pads are categorized into three: air, self-inflating, and closed-cell foam. Let’s differentiate and see where each type is best suited for use.
Air pads: Among the three types, air pads have a wide range of options; from lightweight for backpacking to mattress type for camping. Air pads are manually inflated are the most compact of the three types packing down to almost the size of a regular Nalgene bottle. Some may come with a built-in pump attached to the pad or a separate pump like the Nemo Tensor Ultralight that has the Vortex pump included in the pack.
Air pads are the top choice for backpackers due to their compact size and weight. However, air pads are very susceptible to punctures and require extra care to last. Some air pads provide patch kits to alleviate this.
Self-inflating pads: These sleeping pads offer a combination of open-cell foam insulation and air. Opening the valve allows the air to automatically enter. When the sleeping pad is unrolled, the foams are decompressed allowing the air. Some pads have dual-valves like the TRAZON Camping Pad that allows quicker inflating and deflating.
Self-inflating pads like the TETON Sports ComfortLite offer more cushioning than air pads but comes at a heavier weight than its air pad counterpart the TETON Sports Adventurer.
They are more puncture resistant than air pads and often firmness can be adjusted by simply adding or releasing air via the valves.
Foam pads: The third type of sleeping pads are the closed-cell foam pads. Unlike the open-cell foam pads and the air pads, the closed-cell foam pads are the least to be punctured. They are made from dense solid foam with tiny closed air cells. They are lightweight but due to the dense solid foam, the least comfortable of the three.