Timber refers to the wood used for construction and several engineering and other works. The word Timber is derived from the old English word 'timbrian' that means 'build'.
Living tree solid timber is known as Stationary Timber, and after falling and separated from the trees, it is known as Rough Timber. After the log is seasoned and converted, it is known as Converted Timber.
Here are some of the market forms of timber explained below:
• Log
Trunk, Stem or wooden axis of a tree is cut, and then it is known as a log. It can be converted and used as firewood and lumber, etc.

• Deal
Deal is a type of softwood, usually obtained from Scott pine trees, sawn with parallel sides of thickness 2 inches to 4 inches, and of width 9 inches to 11 inches.

• Baulk
Baulk is a piece of timber obtained by removing the bark and sapwood, which looks roughly square-shaped. The cross-sectional dimensions are usually more than 50 mm on one side and more than 200 mm on the other side.

• Plank
It is a long timber piece with parallel sides of width more than 50 mm and thickness less than 50 mm.

• Batten
A Batten is a strip of timber, of thickness 2 to 4 inches and breadth 5 to 8 inches. It is used in roofing, flooring, ceilings, wall and other construction applications.

• Boards
It is a plank of timber with parallel sides, thickness not exceeding 50 mm and width exceeding 200 mm.

• Scantling
Scantlings are pieces of timber with different sizes. Depending on the type of work, they are sawn out of a log and cut into required sizes. The thickness and breadth are more than 50 mm but limited to 200 mm.

• Pole
Pole is also known as Spar, which is a long log of diameter less than or about 200 mm.

• Quartering
These are square pieces of timber, consists of length vary from 50 mm to 150 mm.
• Strips
Strips are wooden pieces of a thickness not more than 50 mm and width not exceeding 100 mm.
• Post
It is a rectangular wooden piece used as a compression member in buildings, having a diameter less than 300 mm.
• End
The small pieces of battens, deal, poles or scantlings are referred to as Ends.

The use of timber for engineering aspects is due to its exclusive properties like:
- It is ready to use material available naturally, used for temporary works like scaffolding, centring, shoring and strutting.
- It is widely used for doors, windows, flooring and roofing as it is easily convertible into any shape and size.
- It possesses excellent strength and a good preference for making load bearings like columns, beams, trusses and piles.
Check Out: How to Check the Defects in Timber