Machine Stitches

Hi... I am new here, so forgive me if this has already been discussed somewhere.  I have a Kenmore machine.  Not sure how old it is, it was a hand me down from my grandmother.  It works just fine, but I don't have the manual, and my problem is that I have no idea what some of the stitches do or what kinds of sewing they are good for.  I'm trying to learn to sew with knits right now and am think more than just a straight or a zig zag might be helpful.  Is there any sort of reference for these things?  I appreciate anyone's help!  Thanks in advance!!

I've tracked down some manuals using this site: http://www.sewusa.com/Sewing_Machine_Manuals/kenmore_Sewing_Machines.htm.  They might have a manual for your machine some of which can be downloaded for immediate reference. 

Thank you so much for your help!  I really appreciate it.  Hopefully I'll be able to track down an manual.

thanks again!