Joins Tutorial Anywhere?

[Rich]

Hi folks.  Any chance on a tutorial from joins?  I find them totally
confusing and I know there's some power in them, so I need to learn them.

Having asked that, another question arises...do my field names in different
tables within the same database have to overlap (same field name) in order
for joins to work?  I'm currently naming fields in such a manner:

TABLE1
table1_alpha
table1_bravo

TABLE2
table2_firstname
table2_lastname

Appreciate any guidance on these two questions.

Cheers