What is lube and how do you use it?

[Hawner]

Lubricant is any kind of substance, normally liquid or creamy, that allows for less or even no friction between two surfaces.
It is used in machinery to avoid friction between metal parts, which would eventually break cause of it, or on any two parts that fit together.
I am going to guess by context that the lube you mention is for sexual use. In this case, you apply it on the penis and/or the vagina you the penetration meets less resistance.
There are woman that do not create enough of their natural lubricant, which during coitus creates problems. Friction between two dry skins tends to be painful, and that area is very sensible.

[Jac2424]

Lubricant- it helps things slide where they need to. Not always necessary. Ask me if you like to know more :)

[Agape93]

You’re joking right