18650 / 20700 / 21700 / 26650
These numbers, when it comes to vaping, are battery sizes. The most commonly used battery for powering vapes is 18650, though you will run into a mod that utilizes one of the other battery sizes from time to time.
510 is a reference to the size of the connector that your tank utilizes. The 510 connector is the protruding pin located on the bottom of the tank which screws into the vaping device. Nearly every tank and device on the market uses a 510 connector, so you won't run into other sizes often, if ever.
This is a very common smaller bore (8.5mm wide) drip tip size. It is used commonly in mouth to lung devices and lower powered sub-ohm tanks.
This is the most common larger bore drip tip size. It measures at 12.5mm wide and is most commonly used with higher powered sub-ohm tanks and RDA's.
Analog is a word used by the vaping community to refer to traditional cigarettes.
When a device has this feature, it means that you don't have to press a button in order to vape, you just put your vape to your mouth and inhale. This function is created by using a switch on the battery that responds to pressure created when you inhale. The battery then fires upon activation by that pressure switch, heating up your coil and creating vapor. Auto-draw is most often found in pod systems.
A box mod is simply a mod with a boxy and rectangular shape. These can come in a variety of different sizes and styles, and can have either replaceable or built-in batteries.
When it comes to vaping, a cloud is the vapor exhaled from an electronic cigarette.
The coil is a metal resistance wire paired with wicking material. When an electrical current is passed through the wire it heats up and vaporizes the juice contained in the wicking material. This is how you get fat cloudz.
Coil Head (or Atomizer Head)
A coil head is a prebuilt coil and wick contained within a metal housing. These are used utilized by nearly every popular tank on the market, each with their own proprietary coil heads, and sold as replacement coils.
Direct lung describes a vaping style in which the user quickly inhales a lot of vapor directly into their lungs, similar to taking a deep breath. Though you can exercise direct lung vaping with basically any device, it's usually a requirement while using more powerful devices, as they produce a lot of vapor and heat.
This is the mouthpiece of your vape, which you wrap your lips around and inhale vapor from. Drip tips are usually replaceable, come in a large variety of styles, and are made with anything from plastic to resin to gold. Most drip tips are one of two sizes: 510 or 810, with 810 being the larger of the two. The size of your drip tip will typically be found in the instruction manual of your tank or device.
A dry hit is what occurs when your wicking material isn't saturated well enough with juice, causing your coil to burn the material, resulting in the exceptionally foul taste of burnt cotton, usually accompanied by uncontrollable coughing for a minute or so and the desire to never experience a dry hit again.
E-Liquid (aka E-Juice/Juice)
eJuice is, in the most basic terms, what you vape. It is made up of propylene glycol, vegetable glycerin, flavoring, and, usually, nicotine. It is the life blood of your vape and is available in an endless amount of flavors created by an innumerable amount of manufacturers.
Flooding occurs when too much juice makes its way into the wicking material of your coil. It's usually accompanied by gurgling, spitting, and leaking, so you'll know when it happens.