To understand why Linux has become so popular, it is helpful to know a little bit about its history. The first version of UNIX was originally developed several decades ago and was used primarily as a research operating system in universities.
Usage Note: Disabled is the clear preference in contemporary American English for referring to people having either physical or mental impairments, with the impairments themselves preferably termed disabilities.
Disability: any restriction or lack (resulting from an impairment) of ability to perform an activity in the manner or within the range considered normal for a human being. Handicap: a disadvantage for a given individual that limits or prevents the fulfillment of a role that is normal.