Peruse this gallery of the various types of fasteners used in woodworking projects.
Common wood screws are made of steel and normally have a rust-resistant zinc coating. Flathead wood screws (FHWS) are made to be driven flush with the surface. You also can counterbore them into a hole in the surface and cover the screw with either a wood plug or wood putty so the fastener is hidden. Oval-head and roundhead wood screws (RHWS) protrude above the surface for decorative effect or a finished look when fastening metal hardware. You'll also choose from three common screw-head slot types: slotted, Phillips, and square drive. These match different screw-driving tools.
A trim-head screw is a thin, case-hardened, double-lead screw with a small head used in place of a finishing nail when fastening trim. Drywall screws, also called case-hardened steel screws, have a skinny shank and a dull black finish. They're exceptionally tough and are most often used with a power drill-driver. Case-hardened screws come in two thread configurations. One-thread single-leads hold best in softwoods and particleboard. Double-leads have twin threads that bite into hardwoods better.
Hanger screws have a wood-screw thread on one end and a machine-screw thread on the other. This allows you to screw one end into a wall stud, for example, and use a nut and bolt on the other. Both of these fasteners are useful when attaching heavy cabinets to a wall. Lag screws are heavy-duty fasteners that have a threaded shank like a wood screw. They have a hex-head like a machine bolt that allows you to use a wrench, rather than a screwdriver, to apply more torque when tightening them.
Screw sizes are easy to understand. The gauge indicates the size of the shank diameter in a range from #0 (smallest) to #24 (largest). Gauge increases about 1/64 inch in each size increment. Lengths begin at 1/4 inch and extend to 4 inches and longer. Each length comes in three or more gauges. The thinner the wood, the smaller gauge screw you need.
Finishing nails are thin, small-headed nails used for fastening molding and other interior trim. The heads are usually countersunk below the wood surface. The resulting hole then is packed with wood filler. Use casing nails where the heads will be exposed to moisture. Brads have heads like finishing nails but are much smaller.
Although many types of adhesives are on the market, including epoxies and instant-bond glues, the best all-purpose glue for most woodworking projects is aliphatic resin (AR) glue and modified formulas of it. AR glues are premixed, so you apply them from squeeze-bottle containers. They come in white (PVA), yellow, and darker tints for dark woods. They're strong, and they dry in about three hours. (The white variety dries more slowly, giving you extended time to work.) Newer formulas provide extended water resistance. Shelf life is about six months to a year if refrigerated (but not frozen) when not in use.
Polyurethane glue is gaining favor with some woodworkers because it performs much like epoxy without the mixing and the strong chemical odor. It's waterproof too. You'll pay more, however, for polyurethane than AR glue.