I am by no means an expert but here is what I understand in brief.

Slalom fins / sails. The fins allow for more lift, are harder to gybe and perform better in straight lines, the sails have cams to lock the draft in a forward position, are harder to rotate but keep power up through lulls and control gusts better.

Wave fins/sails. The fins are swept back to allow for better turning, dont perform well in straight lines as slalom and are a lot slower at accelerating. The sails are easy to rotate and are rigged quite flat usually - they feel a lot more on/off than freeride/cammed sails. Sails are usually made from stronger material, often with xply in.

Freestyle fins/sails. The fins are short like wave but newer ones are not swept back - more of a trapezium like shape, allowing for backward sliding moves. The sails are often like the wave but lighter construction for more flicky/faffing stuff.

Freeride is just a combination of it all - the fins are longer like slalom, but have a slight sweep allowing for easier carving moves, the sails have quite deep profiles but no (or maybe a couple) cams.

razzmatazz said...

another question or two to the venerable and knowledgeable membership of seabreeze.

Sorry, please ignore my last comment. I certainly don't fit your requirement.

I gather that you mean can you use sails on the same mast?

If so, then yes, up to a point.

Bascially (and this differs with different brands) smaller sails set on smaller mast - say 4m-5m on 400, 5m-6.5m on 430, 6.5+ on 460 etc. BUT some brands now require reduced diameter masts (RDM or skinny) for their wave sails - the luff tube will not fit a standard (SDM) up it.
As the sail gets bigger so does the boom length, usually 2 booms will fill all your requirements - a 150-200 and a 180-240 (to not put too much strain on a fully extended boom I prefer to use a bigger one for my 6m and above even though it would fit on the smaller).

BUT it does get more complex......
There are different bend characteristics of masts - the brands differ in other words.
Some sails require a mast with a flex top - some a constant curve, some a stiff top.
This makes a lot of difference to the tunability of the sail, when you get it correct you really notice the difference and when it is wrong your sail will not perform as well as it should - like putting road tyres on a mountain bike or vice versa.

So in short keep to one brand for mast and sail until you have done it a while and start to understand the complexity of it all (or dont bother learning all the brands and just stick to one, im from the UK but love your home brand of severne - the gators are brilliant all round sails!)