a Wooden saw is designed to rip-, meaning it cuts wood along the grain. They meet the wood at close to a 90-degree angle, which causes them to bite aggressively. A shallower angle would let material slide over the teeth more easily, helped by the ramp of the teeth’ slope and the large “gullet” between each tooth also helps carry sawdust out. The teeth on a rip saw are essentially a row of chisels.
<==See more here on Hand Saws for Wood==>
Sawdust from a rip saw is like a bunch of little chisel shavings
The Crosscut saw is different because the wood has different weaknesses across the grain than along the grain, and the angle is also shallower because these teeth are designed to slice through the fibers rather than scrape through them as the rip saw.
Conventional wood saws, need sharpening and resetting regularly and not really worth the effort. European style wood saws are designed to cut on the forward stroke, but Japanese cut on the backward stroke and is designed to leave a cleaner finish, especially on the first stroke as it pulls the fibers into the wood rather than away
Western-style wood saws almost always cut with the push stroke. Japanese style saws cut with the pull stroke; allowing for a much thinner blade.
When ripping wood which has been placed flat, a push stroke saw runs more smoothly than a pull stroke, since the grain is “downhill”.
For metal, the direction is irrelevant.