Main Difference
The main difference between Hardwood and Softwood is that the Hardwood is a wood from dicot trees and Softwood is a wood from coniferous trees, or Ginkgo
Hardwood
Hardwood is wood from dicot trees. These are usually found in broad-leaved temperate and tropical forests. In temperate and boreal latitudes they are mostly deciduous, but in tropics and subtropics mostly evergreen. Hardwood contrasts with softwood (which is from gymnosperm trees).
Softwood
Softwood is wood from gymnosperm trees such as conifers, as well as Amborella. The term is opposed to hardwood, which is the wood from angiosperm trees.
Hardwood (noun)
The wood from any dicotyledonous tree, without regard to its hardness.
“Balsa is a hardwood, but a soft hardwood.”
Hardwood (noun)
(in more general use) As the preceding but limited to those that are commercial timbers, and are at least average in hardness.
“Ash, hickory and oak are some of the most prominent domestic hardwoods.”
Hardwood (noun)
The tree or tree species that yields the preceding.
“This hardwood has been planted extensively throughout the hills here.”
Hardwood (noun)
A joint term for the commercial timbers, without distinguishing which.
“You should have used hardwood for this window sill instead of this junk.”
Hardwood (noun)
The sport of basketball, in particular, an indoor basketball court; so named because the floor of an indoor basketball court is normally made of hardwood.
Hardwood (adjective)
Of a floor: made of interlocking hardwood boards.
Softwood (noun)
The wood from any conifer (or from Ginkgo), without regard to how soft this wood is.
“SYP is a softwood, but it is harder than many hardwoods.”
Softwood (noun)
Wood of this kind but limited to those that are commercial timbers.
Softwood (noun)
The tree or tree species that yields this wood.
“This softwood has been planted extensively throughout Scotland.”
Softwood (noun)
Any commercial timber.
“You should have used softwood for the frame of this shed, instead of overbuilding it like this.”