As I have mentioned many times before, I am an avid woodworker. Although not good enough to do classes on the subject I want to share the knowledge that I have gained from this outstanding hobby.
There are several basics that every woodworker should know. The main one, before a saw is put to wood, is to know your wood. This decreases the chance of accidents and will allow best selection for maximum beauty in the project.
There are two types of basic wood: hardwood and softwood. Softwood comes from the evergreen trees (coniferous) that you see in the norther hemisphere. Examples of softwood trees are pine, spruce, cedar, fir, larch, and douglas fir. When it comes to working these woods they tend to be easy to cut and carve but tend to be weaker woods due to the lower density of the material. These softwoods can make great furniture but most fine furniture makers will use the hardwoods.
Hardwoods are mostly from deciduous trees such as mahogany, teak, walnut, oak, ash, elm, aspen, poplar, birch, and maple. These woods have a much more dense structure making it harder to work but the furniture you make from it will be ready to last for eons.
How are these measured and sold? That is dependent on your choice of wood. Most hardwoods are sold by the board foot (bft). You will see it labeled as 2/4, 4/4, 6/4, or 8/4. What does this mean? It is a label in inches 4/4 equals 1 inch thick, 8/4 is 2 inches thick. You will still have to select your width and length. Other woods are measured in the common 2 x 4, 3/4 x 6, ext …, where the first number is the thickness and the second the width. All you have to select is your length.
No matter the wood you choose, all woods can be beautiful if used in the right project. I suggest going down to the local hardwood store or lumberyard and looking around, you will find that seeing the process is much more descriptive than just reading about it.