Explain equal and identical objects

[olexandr-konovalov]

This example may be confusing for new users, important we cover it:

gap> a:=[1,2,3];
[ 1, 2, 3 ]
gap> b:=a;
[ 1, 2, 3 ]
gap> a[3]:=35345345;
35345345
gap> a;
[ 1, 2, 35345345 ]
gap> b;
[ 1, 2, 35345345 ]