What IT jobs exist but are less well-known?

May as well list as many as I can, since I don't see any other responses:

Business Analyst - assists end users in defining the inputs and outputs of their technology.

Developer - turns the inputs into the outputs

QA - verifies the inputs turn into the expected outputs

Infrastructure - makes sure there's a place for the inputs to be put into.

Network engineer - makes sure the place for the inputs can be gotten to.

DevOps - makes sure the input/output generator gets to the place infrastructure set up.

Operations (workflow) - in charge of a big clock, makes sure things happen when they're supposed to

Security - makes sure the only inputs and outputs are the ones that are there on purpose.

Data - ensure inputs/outputs are saved for later retrieval

Data analytics - find patterns in the input/output pipeline

Application support - when the input/output device is brought in from an outside source, this person makes sure it runs as expected

General support - addresses the case where a user has a problem with their inputs/outputs

UX designer - makes sure the experience of inputting the inputs and consuming the outputs is a pleasurable one.

Designer - designs the input/output interfaces

Compliance - makes sure the inputs/outputs are within the boundaries of the law, and in the grey areas makes sure the process has good intent.

Architecture - makes sure the reason for the input/output process is inline with the direction of the company.

Change control - ensures changes to the input/output pipeline don't conflict with the greater environment

Project manager - makes sure all of the above people work together to complete their task

If by IT you also include all tech jobs, I'd include hardware companies that also need software. Many of these companies may not have much sw expertise and can provide a great learning experience, including low level coding and hardware interfacing.