RTA, RDA, RDTA - lots of confusing terms but once you understand the basics then it all becomes a little clear.
RTA stands for Rebuildable Tank Atomiser - all that means is that the coil is rebuildable. The benefit of this is that you tend to get better flavour and are able to rebuild coils to your own specification rather than relying upon what the manufacturer gives you in a pre-built coil.
The image to the right is an example of the various configurations you can have with an RTA.
Many RTA tanks come with a single coil deck and a dual coil deck.
The twisted wire is the actual coil - this tends to last quite a while - certainly longer than a pre-built coil because you can remove the cotton, burn off the residue then simply re-fit the cotton - this is known as 'wicking' or 're-wicking' if you prefer.
There are a number of types of RTA deck - velocity, GTA, etc - the designs are constantly changing. Most experienced vapers will use and RTA or RDA (dripper) because of the flexibility of being able to change the coils and cotton to their own spec and the resulting benefit in terms of flavour or cloud.
Beginners typically don't start with an RTA purely because there is a little more maintenance involved - it takes minutes to re-build but when you're starting out it is easier to simply screen a new pre-built coil into a tank.
Vaperscape always carries a broad range of RTA tanks such as the Troll, Kylin and SMM. We ourselves use RTA tanks so are usually using the best in class* or newest bits of kit.
*Not everyone agrees on which is the best due to personal preference - air flow, noise, ease of build, flavour, etc are all characteristics that are subjective depending on your own needs.