Table saw safety and preventing kickbackThe table saw is arguably the most dangerous tool in the shop. You should treat it with respect, however, there is no need to be afraid of it. Instead learn how to use it safely and that means preventing kickback. (More on woodworking safety here). That means among other things: * understanding and preventing kickback * using push sticks * using a miter gauge for cross cuts * making sure your wood is properly milled *using a splitter or riving knife *and, most importantly, working smart. Let's start with kickback. Most people know kickback is dangerous, but often people don't understand why. Kickback happens when the wood hits the back of the blade or the wood binds. Common causes of kickback are: *the kerf closes behind the cut pinching the blade In each case, the velocity of the spinning blade can lift the board and send it flying. I've seen a piece of wood fly so hard it stuck in a plywood wall. You don't want to be hit by that! (Perhaps this is an opportune time to mention safety glasses.) Preventing kickback can also save fingers. People do serious injury to their hands when the blade grabs the board pulling it and the hand into the blade. Kickback is over before you are even aware it happened, so don't think you can react in time to pull your hand out of the way. You can't. Instead learn to prevent kickback altogether.
When I first learned woodworking I worked at a shop that didn't have push sticks. I remember being a bit nervous about cutting 2" wide stock, but everyone else was doing it, so it must have been safe, right? The shop did nothing to prevent kickback. I was lucky. You might be too. Then again, luck is notoriously unreliable. So, please use appropriate jigs and push sticks.
The best way of preventing kickback is to use a riving knife or splitter and an anti-kickback device on your table saw. An anti-kickback devise holds the wood down against the table so it can't fly across the room. They are a good way to prevent kickback from being deadly if it does happen. New table saws are finally starting to come with decent safety equipment that can help prevent kickback. If you have an older model table saw your options are more limited. You can sometimes find an aftermarket splitter (the one in the photo below is an inexpensive solution).
I have yet to see a decent after market riving knife. Be aware that the dust collection systems on the market help keep fingers from traveling into the blade, but mostly don't do much to actually prevent kickback. Look at the specifics before getting one. Other ways to help prevent kickback are to make sure your wood is flat and the side against the fence is straight. Keep your blade parallel to the fence. Never try to free hand a cut. I've seen it done a couple times. I think the people doing it are nuts.  In the same vein, don't use the fence when cross cutting narrow stock. There isn't enough wood against the fence to control the cut. Instead use the miter gauge to push the wood and leave your table saw fence to the side. If you need to have a stop, either clamp one to your miter gauge or clamp a short piece of wood to the fence. Butt your stock against it to get your measurement, but make sure the stop is behind the blade. You don't want to get the cut-off trapped between the blade and the fence. These are a few things to think about to help prevent kickback when using a table saw. Keep your blades sharp and your mind sharper.
The table saw is one of the most useful tools in the shop. Learn to prevent kickback and it can also be perfectly safe.
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The riving knife and splitter will hold the kerf open behind the blade so the wood can't close on the cut. If the kerf does pinch the back of the blade...wheeee - there goes the board. 
