Atty = Atomizer. It is most akin to a toaster coil. It's a very thin coil that heats up whenever you press the battery's button.
Toppers = tanks.
Tanks = things you put your liquid into that contains the atomizer.
The best analogy I can give for how atomizers work is to think of a lightbulb. We all know how to swap out a lightbulb. And it is essentially the same concept. The coil gets hot, hot, hot, hot, then it finally pops. Swapping one out is just like swapping out a lightbulb.
"Toppers", "Tanks", "Atomizers", and "juice" are all encompassed in one device, the "tank". It combines all those elements.
Ohms: a resistance rating in electronics. I am not a electronicist so I can't describe it further. A general rule of thumb: if you know the resistance of your atomizer, just add TWO to that number. For example, if you ask and they tell you your atomizer is at 2.0-2.2 ohms, add two to that number. If you have a Twist or a Spinner battery, you'll probablty find the best performance around 4 volts. 2+2=4.
VV = Variable voltage. This is like being able to turn up the volume on your stereo. Only in e-cig style. You can control the amount of power your battery puts out. What this does, essentially, is add more heat to your atomizer coil. This vaporizes more liquid more quickly, giving you more of a hit. Many people consider this an upgrade. Too much heat, though, and your juice can taste burnt and you can "pop" your atomizer coil more quickly. This is why VV is advantageous. You can fine-tune your "sweet spot".
VW = Variable wattage. Similar to VV, only if you find your sweet spot in wattage, you can slap any "topper" on there with any resistance (measured in Ohms) and it will automatically adjust the voltage to your preferred settings.
EGO: Any of the batteries that are shaped like a magic marker that has threads on top and a button.
Battery: the long piece with the pushy button that provides power. It is rechargeable.
Juice, E-Liquid, Oils: This is the actual liquid that contains flavorings and nicotine.
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