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.
The SSA's Definition of Disabled. In the context of Social Security, the definition of disabled is a long-term disability that renders you unable to work in any capacity. You must not be able to engage in any substantial gainful activity (SGA) because of a physical or mental medical condition.