TANKS & RTAS
A tank typically is a glass or plastic reservoir that holds you eliquid. This reservoir has a coil that is premade and interchangeable, some tanks have varying coil resistances which affect vapour production (typically the lower the resistance the more vapour). Many tanks have an adjustable airflow so you can choose how much air mixes with your vapour, altering the flavour and volume.
A RTA is similar to a drip atomiser with the additional convenience of having a tank attached. Instead of having a premade coil, RTA's have a build deck, designed for you to build your own coils. Due to their technical nature RTA's are for advanced vapers.