SDIA definition
Mariam Webster Dictionary defines Information Technology (IT) as
the technology involving the development, maintenance, and use of computer systems, software, and networks for the processing and distribution of data (Mariam Webster)
Other definitions
Gartner defines Information Technology as:
“IT” is the common term for the entire spectrum of technologies for information processing, including software, hardware, communications technologies and related services. In general, IT does not include embedded technologies that do not generate data for enterprise use.