Solid wood is a direct tree extract processed to usable forms such as planks, posts, blocks, etc.
The term softwood may be properly applied only to evergreens or conifers (cone bearing) trees with needle-like leaves, such as pine, cedar fir, etc. Softwoods, on the other hand, are gymnosperms. These plants let seeds fall to the ground as is, with no covering. Pine trees, which grow seeds in hard cones, fall into this category.
All leaf shedding trees are considered hardwood, whether the wood is as soft as poplar or as hard as maple or oak. Hardwood trees are angiosperms, plants that produce seeds with some sort of covering. This might be a fruit, such as an apple, or a hard shell, such as an acorn.
The term “Engineered wood” is used to describe a range of derivative wood products which are manufactured by binding together wood particles, fibers or veneers with adhesives to form a composite material.
Plywood is a type of engineered wood made from thin sheets of wood, called plies or wood veneers. The layers are glued together, each with its grain at right angles for greater strength.
HDF is a high quality panel manufactured from specially engineered fibers that are compressed under heat and pressure. It is similar to particleboard and medium-density fiberboard, but is denser and much stronger.
Particle board or Chip board is a board made from graded wood chips / saw dust / wood particles bonded together with an adhesive under great pressure & heat. The constituents are similar to MDF but with a low density.