Help with Joining two SharePoint lists using LINQ

Hi Guys,

I have found many threads with this question. Although I had one doubt. I wanted to know that while performing a Join operation on two SharePoint Lists using LINQ does the column on which we are performing the join operation need to be a Lookup column?

I was initially using CAML but since my lists does not contain lookup columns I switched to LINQ but my doubt still remains.

I would really appreciate any help from you guys and also would appreciate if I could get some examples that I could refer to.

Thank you