This is a broad and encompassing term that covers the entire structure, which can vary wildly, of your I.T. department. This includes everyone down to the "paper/toner techs", all the way up to the CIO (Chief Information Officer) in C-suite (if so equipped).

The people you will see the most often will be what we generally regard as Tier 1 - in the roles I've had or encountered they have been called Paper/Toner techs (beginners who start off working for a contract company delivering paper and toner to printers across the company), CSRs (Customer Support Reps), HSTs (Hallway Service Techs), Helpdesk, Tier 1 Support, and many other varied names. These people are generally the front-line of support and the first people you will encounter in an I.T. support scenario, and are there to take care of the various simple issues (Out of Paper, Paper Jams, Out of Toner, Password Resets, Network Access Issues on a per-user basis, e-mail problems, issues getting Microsoft Office to do what you want it to do, Windows running slowly....just to name some of the more common ones). This is where you will start out, doesn't matter if you built yourself an entire Domain network in your apartment complete with a mail server, P2P sharing server, network shares, a enterprise grade firewall, all being served off a Cisco Catalyst switch you administer through a terminal emulator program from your Linux workstation, the industry doesn't give a rats ass about that, they want to see what you can do first.

Higher tiers of helpdesk usually include people we call Tier 2, or Tier 3 usually. These people go by names of things like DSSG (Desktop Senior Support Gurus), Senior Techs, Senior I.T. Support, Tier 2/3 Support, or whatever else they can come up with. They are usually paid more, have more experience, proven that experience in the field (if it's a good company and not gatekeeping upward mobility too much). Generally, these folks will be a little harder to get ahold of because they will be sitting in the back of a room or office somewhere working on the harder issues - those that fall between systems/network administration, and tier 1, ie. the issues that Tier 1 can't figure out, or even sometimes, smaller Network/Systems Admin issues that will fall on Their 2/3/etc. because Network/Systems administrators have some hefty work to do (and a lot of phone calls to take, and politics to work with).

Next up are your system admins and network admins. These Administrators are the ones you don't see as they will be spending the day talking to the various 3rd parties involved in maintining the servers and infrastructure of the company's network. They could be talking to people from an entire alphabet soup of companies discussing such major issues as DMZ (Demilitarized Zone - aka, that space between the company's network and the internet), firewall ports and access (with big politics involved in the decision to open ports that maybe Network Security at the corporate level deemed unsafe to open), running updates on servers (a whole hell of a lot different than running updates on a "user" workstation as it can sometimes mean network or a particular in-company network service interruption during the reboot), figuring out about various proprietary data being sent in and out of the company's network, and even within the company's network. It also involves racking and stacking servers, switches, routers, Wireless Access Points (WAPs), and sometimes even coordinating with Tier 2 or 1 to assist with such projects. They also are going to be the grumpiest of the lot because they deal with a lot of conflict, budgetary, and potential legal-related mitigations through some days.

Next are the Supervisors and/or Managers who are the ones that manage those below them, and are somewhat parallel to the administration group we just talked about. They may be technical, they may not. Typically, if they understand technical stuff, it's going to be a far better, far smoother running organization (assuming they keep that information current and up-to-date), than one that hires someone in a suit and tie with no tech experience and an MBA to do the job. This is where Tech and Business truly meet, and it can be a VERY tricky plate to keep spinning when business says "we don't have the budget" or "what is the purpose of this (very useful) thing", while tech will say "if we buy this (super expensive widget) it will make (list of improvements)" or "it does (list and details on things that it does, mostly mentioned in terminology people call "greek" or "geek" dpeending on who you talk to)".

And up from there you have maybe a Director, and then a CIO. Possibly sandwhiched between, in bigger corporate environments, you might have an entire separate "corporate" I.T. team that acts as a central establishment for standards of technology and practicies within the organization, while upholding the main hub of operations wherever that may be based if it's a huge company. These typically include people with even higher levels of experience and/or education to fill the seats in between them, the local directors, and the Chief Information Officer. There may also be two of those too - one local, and one at "corporate".

And for those of you not in the field and reading this for fun, that would explain why some of the people you encounter asking for a password reset or a piece of non-standard software might be a bit grumpy, if not irate at your request in an attempt to circumvent the ticketing system. Because any tier above 1 or 2 is probably going to send you back to Tier 1 for that to fill in a ticket, unless it's something urgent like a "Security Event" (large scale Malware/Ransomware/virus attack that puts the company at risk) - then we might all be really happy you actually told us something, that is, if you're not making getting a spam e-mail in Outlook out to be a ransomware attack because you don't recognize the sender.

So what makes a good I.T. person? Well, it depends on the role, and your ultimate endgame.