There are various levels of desktop support. They start from Level 0 to Level 4. Level 0 being the lowest and Level 4 the highest level of support. Please note the short description below:
Level 0: This is the most basic level where the user can resolve their own issues. These may include resetting passwords, accessing user manuals, internal knowledge base, FAQs, and forums. For example, if a printer is short of paper, nobody calls the IT guy to refill the paper tray.
Level 1: This involves resolving basic issues which do not fall in the Level 0 category. The problems that they are required to solve are like assisted password reset, printer fixes, Windows support, etc. They are also required to escalate any issues to the next level if they are not able to fix them.
Level 2: Issues like Windows and software installation, as well as hardware support, is handled at this level. For example, if a computer is running slow then IT support may upgrade the RAM to counter the problem.
Level 3: Any other difficult issues which were not resolved will be escalated to in-house experts. They may be systems administrators, network administrators, or even data administrators. Many companies will have a single person handling such issues. They are expected to resolve issues pertaining to the domain, network, or any other widespread issues affecting one and all. An example here will be to patch all PCs in a domain or sub-domain for cyber security.
Level 4: Issues which require assistance from vendors are categorized as Level 4 support. A common example will be of an internet downtime. The internet service provider can only resolve these issues.