As defined by Peter Drucker, in the 1950s, knowledge worker is a "high level employees who apply theoretical and analytical knowledge, acquired through formal education, to develop new products or services". 

Knowledge workers make decisions rather than physical items and work with ideas rather than with objects. Work focuses on mental rather than muscle power and is characterised by non-repetitive tasks.

Knowledge Workers is the fastest growing segment of workers: it includes programers, lawyers engineers etc .... 

1. Specialists: They know one area very very well. These individuals can be thought of as housing vital corporate assets in their heads.
2. Portable knowledge workers: possess information of wide & immediate utility, that is in demand by a variety of orga...