Appending Assets From One .Blend to Another (Not to be confused with Linking!)

This guide demonstrates how to get assets from one .blend file into another using the Append function.

Even though I'm using Blender 2.83 in this demonstration, this process has not changed over the development of Blender. The process is the same in Blender 2.7x, 2.8x and now 2.9x.

Appending Objects Is a Simple Process of 4 Steps

As they say, pictures are worth thousands of words, so here's a pictorial of the process
And Done!

[Pte Jack]

Yup, Thanks God Splitter, your right. I'm still not fully into what you can do with collections yet. In some ways they are a Gawd send and yet in others, they're the Deevil's spawn.
To be truthful, I still really miss scene layers.

[Janfon1]

I've been using this way of appending since forever, but there's an easier way if you just want the whole thing appended, put it in its own named Collection and append that. If he has custom bone shapes, select their collection, too.