Shareware is a derived term of share.
In context|computing|lang=en terms the difference between shareware and share
is that
shareware is (computing) a type of software that is distributed without payment but is limited in any combination of functionality, availability, or convenience while
share is (computing) a configuration enabling a resource to be shared over a network.
As nouns the difference between shareware and share
is that
shareware is (computing) a type of software that is distributed without payment but is limited in any combination of functionality, availability, or convenience while
share is a portion of something, especially a portion given or allotted to someone or
share can be (agriculture) the cutting blade of an agricultural machine like a plough, a cultivator or a seeding-machine.
As a verb share is
to give part of what one has to somebody else to use or consume.