Proxy object - what is it?

Support Basics & Interface
1

I’d like to learn about the meaning & use of the word ‘proxy’ or ‘proxy object’
I saw it used when an object was ‘linked’ to a file and then its proxy was created.

I couldn’t find it in the manual.
Could someone help please?

Eddie

2

https://www.blender.org/manual/data_system/linked_libraries.html#proxy-objects

3

Many thanks, Richard. You have advised me before.
Much appreciated.