A team of administrators and other technical staffers deploy and manage the company's IT infrastructure and assets. IT teams depend on a wide range of specialized information and technology skills and knowledge to support equipment, applications and activities. Third-party contractors and IT vendor support personnel augment the IT team.
The information technology profession is extremely diverse: IT workers can specialize in fields like software development, application management, hardware -- desktop support, server or storage administrator -- and network architecture. Many businesses seek IT professionals with mixed or overlapping skill sets.
Source: https://searchdatacenter.techtarget.com/definition/IT