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I was searching about SCD types and the forum has lots of dicsussion about scd's. I came across different dimension types like conformed, degenrative (to name a few) . Can some body please explain the various dimension types.

Ken Bland has given some of more detailed answers on this. Do a search.

A "regular" dimension is one - it doesn't really have a name - that is a parent table to a fact table. That is, the fact table has a foreign key that is resolved in the dimension table.

Conformed dimensions are simply shared by more than one fact table. The time dimension is a typical case - every subject area in the data warehouse uses the same calendar.

Degenerate dimensions record the occurrence of an event, but no other information. These are typically represented by a combination of one or more non-fact columns in the fact table, but no corresponding dimension table. An example is a student attending a class. There is a student dimension, there is a class dimension, but there is another column that records the fact that the student attended the class. Degenerate dimensions usually occur with line item-oriented fact table designs.

A junk dimension is a convenient grouping of random flags and attributes to get them out of a fact table and into a useful dimensional framework.

An excellent book to read is The Data Warehouse Lifecycle Toolkit by Kimball, Reeves, Ross and Thornthwaite (Wiley, ISBN 0-471-25547-5) particularly the chapter "A First Course on Dimensional Modeling".

Thnks a lot.Appreciate your quick responses.