Types of Unreserved Tickets I found till today-
Ordinary (O)
Mail/Express (M/E)
Superfast (S)
Antodaya...
more... Superfast (A)
Mahamana (N)
Mahamana Superfast (M)
Amrit Bharat (W)
Amrit Bharat Superfast (B)
AC EMU (Mumbai AC Local) (U)
Vande Metro (V)
Kindly reply if any other exists.