As vaping becoming popular, more and more people are moving to vaping and often get confused when they hear different technical terms like VG and DTL. In this article, I have tried to explain what this term means.
This is a process of turning liquid into vapour and draw-in the vapour in order to take in nicotine or to enjoy different flavours.
A small device that turns liquid used during vaping into vapour. The device is constituted of a rechargeable battery also often called a mod and a tank that holds the liquid and fitted with a coil that heats up to turn the liquid in vapour 
This is vape kit shaped like a pen with a very basic function. This is ideal for someone new to vaping or one who doesn’t like to change settings like resistance, wattage or temperature that can be done in more advanced kits often referred to as mod kit. Vape Pen kit often comes with a replaceable tank or fixed ones and may have battery charge indicators. Some kits often termed as Mech or Mechanical mod/kits may be shaped like vape pen kit but these are for the more advanced vapers as they have a complicated tank system and unlike vape pen kits hardly have any built-in safety features. 
Like Vape Pen Kits, Vape Mod Kit also comes with a tank and a battery but the battery called Mod is not necessarily shaped like a cylinder but may be square, rectangular or any other shape. Vape Mod Kit may have basic functions like Vape Pen Kit suitable for new vapers or may have additional features like a display or option to change wattage, temperature. The Advanced Vape Mod Kit comes with the option to choose a wide range of coil types.
Vape mods are simply the power unit of a vape kit that contains the rechargeable battery and may have built-in safety features, a display and option to change settings of wattage, voltage, temperature.
Vape Tanks are the unit of Vape Kits that sit on top of the Vape Mods. It holds the E-Liquid and a vape coil that heats up and vaporises the e-liquid
Vape Coils often referred to as Atomizers are the unit in the Vape kits fitted in the Vape Tank that heats up to vaporize the E-Liquid contained in the tank.
RBA or Rebuildable Atomizer is a set of coils build by the user, a deck connected to the coils with the help of screws and cotton plugged into the coils. To vape the user drip drops of e-liquid to wick ( moistened withe E-Liquid) the cotton and vape. After few puffs the cotton dries up and the user has to drip e-liquid again to vape.
RBAs are for advanced users who are confident with building their own coils/atomizers
RDA ( Rebuildable Dripping Atomizer) is a kind of RBA in which user drip vape liquid through the mouthpiece also called drip tip.
RDAs although give a pure dense flavour of the E-Liquid but it is inconvenient to drip e-liquid after every few puffs
RTA stands for Rebuildable Tank Atomizer and is a kind of RBA. It is similar to RDA except that the cotton is surrounded by a chamber with holes and the camber is placed in a tank filled with E-Liquid. The E-Liquid is soaked into the cotton and thus the user can use the RTA as standard vape tank without needing to drip drops of E-Liquid after every few puffs.
The downside of RTA is that if the holes are too small the cotton will may not wicked quick enough and you may get burnt taste or dry hits ( tiny drops of hot e-liquid spitting back into your mouth). Also, if the cotton is not wicked properly the e-liquid may leak out of the tank.
RDTA or Rebuildable Dripping Tank Atomizer is an RBA formed by integrating the functionality of RTA and RDA. In this setting, the coil deck sits at the top of the tank filled with e-liquid and the cotton in the coils get the vape juice from the tank. As the coil is above tank there is hardly any leaking issues and as the user draw-in the vapour directly from the coil just under the drip tip he gets the intense pure e-liquid flavour just like an RDA.
Its is a sensation on the back of the throat that you gets during vaping or smoking. This is one of the factors that satisfy the desire for vaping/smoking.
These are Mods that have got electrical circuit to control Voltage, Power, Current, Resistance and Temperature and are suitable for those who are new to vaping or are concerned about their safety. These Mods come with lots of built-in safety features like Low resistance protection, short-circuit protection, over-voltage discharge protection and so on.
These are mods often termed as mech/mechanical mods that supply voltage direct to coils from the battery and lacks the regulated/control features of regulated mods. As there are no built-in safety features these may not be safe to use for some in-experienced users.
E-Liquid also known as Vape Liquid / Vape Juice / Vape Liquid / E Liquid is the liquid that is filled in the vape tanks or pods to produce vapour.
Most E-Liquid constitute of Vegetable Glycerin (VG), Propylene Glycol (PG), optional Nicotine at different strength and flavourings.
MG/ML is the unit that measures the strength of nicotine present in an E-Liquid. It is the milligram of nicotine present in 1ml of e-liquid. So an 18mg/ml nicotine composition of E-Liquid will have 18 milligrams of nicotine in 1ml of liquid. Standard nicotine composition in the UK is 0mg/ml, 3mg/ml, 6mg/ml, 18mg/ml and 20-25mg/ml
This show what percentage of PG ( Propylene Glycol ) present compare to the percentage of VG ( Vegetable Glycerin ). So a 30/70 PG/VG ratio in an E-Liquid means in 100% pg/vg composition 30% is PG and 70% is VG. Higher the VG percentage denser the vapour/clout and thicker the liquid. Higher the PG value greater the throat hit.
Sub-Ohms Vaping is vaping where the coil resistance is below 1 ohms. Denser Cloud is produced in this mode of vaping. Direct-To-Lungs draw-in done in this style of vaping
Direct-To-Lungs or DTL or DL is a kind of od vapour draw-in where the vape takes the vapour directly into the lungs and exhale it out. This is possible during sub-ohms coils and wider drip tip.
As the name suggests, Mouth-To-Lungs or MTL is a vaping style where the user takes in the vapour in the mouth just like a cigarette and then pass it into the lungs. For this style of vaping the user uses coils of 1 ohms or above with narrow drip tip.
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