Basic e-cig use:
1 - it won't taste like smoking a cigarette. 'Cigarette' flavored nicotine liquid taste like tobacco smells.
2 - Take long slow drags off of the e-cig, into your mouth, then inhale into your lungs. Taking a quick puff off an e-cig like you do a cigarette will not work very well. Don't limit yourself to 'so many drags' from your e-cig; you don't get as much nicotine per drag from an e-cig as you do from a cigarette. Plus you don't have to worry about your e-cig burning / going out

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3 - When the vapor ("smoke") starts to decrease per drag or the flavor starts to go away; it's time to refill the cartridge / cartomizer with nicotine liquid.
4 - I believe the light on the ego will flash when you press the button when the battery needs recharged. So if you take a drag off the ego and don't get any vapor and the light is flashing, time to recharge

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e-cigs come in two basic options:
1 - battery / atomizer (atty) / cartridge (cart) [three piece e-cig]
2 - battery / cartomizer (carto) [two piece e-cig]
Batteries, although they are offered in many different sizes and shapes, come in either automatic or manual. Automatic e-cig batteries contain a tiny switch inside them that turns on when suction is applied (taking a 'drag'). Manual batteries have a button that you push to turn them on.
The atomizer has a small wire in it wrapped around a high temperature wick. When the atomizer is attached to the battery and the battery is turned on, this wire heats up and vaporizes the nicotine liquid that has been absorbed by the wick.
The cartridge (cart) contains a spongy material that holds the nicotine liquid.
A cartomizer (carto) is a cartridge that has a built in atomizer.
The nicotine liquid (
e-liquid,
juice, e-juice) comes in different concentrations of nicotine. Typically for someone who has smoked full flavor cigarettes, 24 mg (24 mg/mL) nicotine liquid is a good starting point. Vendors offer 6, 12, 16/18, 24, and 36 mg nicotine liquids.
The ego is a good starting e-cig (many long time users of e-cigs use egos). The ego is larger than a cigarette (about the size of a cigar); but will also last much longer before needing recharged than the smaller, cigarette-size e-cigs.
All cartridges and most cartomizers can be refilled with nicotine liquid. There are many YouTube videos showing how this is done.
The atomizers and cartomizers come in different resistances. This is just a way of saying how 'powerful' the atomizer/cartomizer is. The average atomizer/cartomizer is in the range of 2.5 - 3 ohms. The lower the ohm number the more 'powerful' the atomizer/cartomizer will be on the same battery.
This isn't something that you really need to concern yourself with when starting out.
Get the basics down first, then you can work on 'tweaking' your e-cig(s) to improve your experience.
Dang, I'm long winded too
Hope this helps, at least some; and doesn't add to the confusion.
Hang in there and when you get your e-cig, and have any specific questions, ask them, that's what we're here for.
