How do I weld parts? How does welding work?

Welding holds two parts together, basically creating a bond between the two of them. Good for holding unanchored parts together.

There are two ways [that I know of] to weld parts together.

Method one,

Create two parts that you want to stick together, it does not matter how far apart they are. Right click one of the parts and insert a new object, either a "Weld", or a "WeldConstraint". Weld is outdated and tougher to use, in my opinion anyways. WeldConstraints are updated welds and are probably better. Anyways, click on the new weld you added, then open the properties tab. Inside it, near the bottom, there should be a tab called "Parts". Open it if it's not already open it and click "Part0", go back to the explorer tab and click on the first part you want to weld. Go back to the properties tab, click "Part1", and click on the second part you want to weld. Congratulations, you've welded two parts together. When you test it, they'll stick to each other.

Method two,

Insert a script into the workspace [make sure it's a script, and not a local script], and type this in

local p1 = workspace.Part1
local p2 = workspace.Part2
local Weld = Instance.new("WeldConstraint", p1)

Weld.Part0 = p1
Weld.Part1 = p2

It's not perfect, but it creates a weld and locks the two parts together. Obviously, you'd replace "Part1", and "Part2" with the name of the parts you'd like to weld together.