There are two main types of portable gas canister stove: “Canister-Top stove” and “Remote Canister Stove”
Canister Top Stoves: Conventional camping / backpacking gas stoves consist of a stove which attaches with a standard screw threaded (7/16th UNEF) connector to a gas canister. They are popular because they are simple to use, small, light and inexpensive. They are the most widely used type of backpacking stove. But there are a couple of drawbacks. The setup is not stable for larger pots. It is difficult to use a windshield without over-heating the gas canister.
Remote Canister Stoves connect to the gas canister with a flexible hose / fuel pipe. This allows the stove to have a lower centre of gravity, so larger pots can be used. The gas canister can be placed a safe distance from the heat of the stove, so a wind shield can be used very efficiently. Both of these features make remote canister stoves safer and more efficient alternatives to canister top stoves.
An additional feature of remote canister stoves like the KOVEA Spider, is that in cold conditions, the gas canister can be inverted (turned upside down). This improves low-temperature performance.
For further details see: “Why use a KOVEA Spider in Inverted Mode?“