Help in using Callbacks

Could someone please give me readings or small examples on how GLPK solver callbacks work?
I would like to test on the model I’m building but I don’t know where to start.

Thanks!

https://jump.dev/JuMP.jl/stable/manual/callbacks/
https://jump.dev/JuMP.jl/stable/tutorials/Mixed-integer%20linear%20programs/callbacks/