A router is one of the most useful versatile tools in any shop. Of course it's not much good without router bits and if you're new to routing, the hundreds of options can be confusing. How do you choose?

Router bits fit into two general categories: edge-forming bits and groove-forming bits.

Edge-forming bits are used to cut decorative profiles on the edges of boards. They are equipped with integral pilots that guide the bit along the edge of the material being cut. Some more inexpensive bits have fixed pilots that are an extension of the bit shank, but most today have ball-bearing pilots that allow the cutter to spin but won't burn the edge of the board as fixed pilots can.

Groove-forming bits cut channels of various profiles into the material. Except when carving freehand, they require a cutting guide. Most basic bits are made with either a 1/4-in. or 1/2-in.-dia. shank. Bits with a larger cutting radius can only be used with a router that accepts a 1/2-in. shank. Unless otherwise noted, the sizes listed below refer to cutting radius.

Straight bits make straight cuts to form a groove or a dado. That's a groove across the wood grain. They can also hollow out an area for a mortise or decorative inlay and they come in a variety of sizes.

Rabbiting bits are guided by a pilot bearing at the tip and they're designed to cut a rabbit or shoulder in the edge of a work piece. Often to join it to another piece. You can buy these bits in a set that includes bearings of different diameters. That means you can cut rabbits of different sizes with a single bit.

Flush trim bits make the edge of one material even with the edge of another. You use this type of bit to trim laminate flush with the material underneath or to route multiple identical pieces with a pattern. Flush trim bits usually have a pilot bearing that's the same diameter as the bits cutter edge.

Forming bits come in different profiles and are used to cut a decorative edge. These include chamfer bits, round over bits, oggee bits, edge beading bits and cove bits. Many of these bits also have a pilot bearing.

There are also a variety of bits made for special applications. You can use sections of multi profile moulding bits to cut different decorative edge patterns. Using style and rail bits and raised panel bits you can make frame and panel doors yourself. Keep in mind though that these bits tend to be larger and must be used in a table mounted router for safety.

Besides the different types of bits you need to know that there are two common sizes of router bit shanks, quarter inch and 1/2 inch. Many routers come with collets for both sizes but some accept only quarter-inch bits. Whenever possible use bits with half inch shanks. You'll get less vibration and they typically produce a smoother cut.

Most router bits have solid carbide cutters or carbide tipped cutters which are harder than high tensile steel and will hold an edge a lot longer but they're also more brittle so handle them carefully. You don't want to drop them.

Router bits designed for the serious woodworker are made with thick high quality carbide and sharpened with diamond abrasives. They are precision balanced and have a non-stick coating to prevent resin buildup.

To make it simple for beginners we suggest a five-piece carbide tip starter set that includes a rabbeting bit with four bearings. A straight bit, a round over bit, a chamfer bit and a Roman ogee bit. All should have sturdy half inch shanks.

We also recommend a set of straight bits in the most common diameters like a three-piece set to match the actual thickness of standard plywood.

Good quality router bits will provide safe and smooth cutting for a very long timeand will help you create with confidence.