Not sure I can add much more to what Baiki said, but maybe I can elaborate some.
The balls are much smaller, I'd say they have about a 16 inch circumference. The balls also weigh about 5 pounds. All balls are the same (weight, hardness), regardless of manufacturer, but are available in urethane or polyester coverstocks. Contrary to 10-pin bowling, it is actually better to throw a slight back-up ball as opposed to a full out hook.
The pins also have rubber rings around their middles which I have no idea what they do (aside from making the pins roll/bounce around more......and maybe it prolongs their life too). The pins can also be attached to strings, which is known as "string-pin" bowling. All the strings do is pull the pins up into the machine, rather than the machine lowering to pick up the pins.
Much like 200+ games are considered good in 10-pin, 300+ games are considered good for a 5-pin bowler. Compared to 10 pins and 7 pins (depending on if you are right or left handed), the corners are harder to pick up in 5-pin. Sparing splits? Ha! Might as well forget about it! The lack of extra pins to deflect the ball/other pins off of make it extremely difficult to spare.
In my opinion, you have to be a lot more accurate to score well in 5-pin than 10-pin, mostly because there is no "oil pattern" or "area" to create hold, but also because everything is much smaller.
If you need any other info just ask, I have a league tonight (10-pin) so I can ask around there for you. Hope this helped,
Jeff
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I can't believe I ate the whole thing......
