I would look up all these great resources and then look at what your pattern suggests. You can then search for the best price for what you need (heavy, medium or light). From what I know (or understand) is that what you are making and out of what type of fabric will determine how much stability you need. Stabilizer=stabilize=stable or sturdy. If you are making a quilted handbag using cotton fabric, you will need at minimum a medium weight stabilizer for the outer wall of the bag (so the sides will hold their shape).
A medium or heavy weight stabilizerwill look like batting, just stiffer and flatter. The outside layerof it will feel more solid as opposed to soft and fuzzy like quiltbatting feels. I just made my first handbag and it called forstabilizer in medium weight. I happened to have something like thatso I just used that. For the portion that called for light weightstabilizer I just used a piece of batting
It worked out justfine. I do recommend using the appropriate stabilizer called for inyour pattern though, it will make a huge difference especially ifyour bag is going to see a lot of use, too light and it won't hold upover time. I am using my bag for knitting so slightly softer isfine. If it were to be used for a purse or travel bag, I would wantto have it be a bit stronger in it's wall construction.
So, that is really what it comes downto. Light stabilizers are more for garments where you want supportto help maintain it's shape but you still want it soft and flexible. Medium is just that, flexible to a point but able to maintain it'sshape more vigorously. Heavy has much less flexibility, holds it'sshape better and can stand up on it's own. Interfacing andstabilizers are two different things. Make sure you are looking atstabilizers.
Fusible interfacing or adhesive paperfor applique are two whole different animals. The adhesive paper isa paper with glue that you first press to the fabric you want to cutyour shape from and then peel away the paper leaving behind the glueon the fabric to then be glued to your project. No support, just asticky film. There is also fusible webbing or interfacing that isoften called stabilizer but usually it is very light weight and ismore for either embroidery or applique. Personally, I hate thatstuff. For me it is useless and ends up messy and bunched. Still,it is there to lend a slight support to the fabric you are working onto help the threads stay even and not bunch especially when doingmachine applique or embroidery...mostly embroidery...but can dependon what type of fabric you are using too. I just did a quick t shirtfor my granddaughter and since the shirt was really stretchy, sometype of interfacing or webbing on the back of the applique would havehelped but I didn't know ahead of time how stretchy the shirt wasgoing to be (ordered of Amazon as no one had it locally) so I did itwithout...ugh...the ONE time I really needed it...oh well, live andlearn and it came out “ok” anyway.
So, check your pattern, see what itcalls for and then check out different brand reviews. I don't evenknow what brand mine was. When I was a newbie (still kind of am) thelady at a LQS sold it to me for a table runner. This stuff was sostiff I couldn't stand it and set the rest aside (it just came off abolt so no idea who the manufacturer was). I held on to it and thatis why I had some for my handbag. I'm thinking that you can prettymuch get any brand medium or heavy as your project calls for and befine. There's not many ways to screw up interfacing/stabilizer.
Well.....LOL!!!
Good luck, hope this helped. Sorry toramble...I'm up early, the house is quiet and my brain is slightlyfunctioning.....it's a good day!