Tek Skills for D&D 5E

In a world with simple technology - anything up to today's level of technology, probably - we can boil down tool/skill checks into two categories: Mech and Tech.

Mech (Mechanical) is the skill that relates to mechanical creation, maintenance, and the like. This is cars, siege weaponry, machine guns, clockwork, lawnmowers, all of that. If it's run on clockwork, gas, or steam it probably uses a mech check to interact with.

Tech (Technology) is the skill that relates to anything you can't really fix with your bare hands and a toolbox. That's computers (both software and hardware), battery technology, and household or professional electronics.

These two categories do not preclude the use of other skills or tool sets to perform specific tasks. For example, a thief may have proficiency in the Security Systems tool kit, which would include both setting up and circumventing technological and mechanical (tech and mech) systems like CCTV, magnetic locks, security PIN pads, laser tripwires, and that kind of thing - anything directly related to breaking and entering and burglary, even if it's normally a Tech or Mech system. Similarly, a character with the Demolitions tool kit may be able to the mine triggered by a laser tripwire and be able to disable it, but wouldn't be able to address a PIN pad - because that doesn't relate directly to explosives.

Common modern tool sets might include:

Security Systems

Construction & Demolition

Automotive

Hardware & Engineering

Software

Gunsmithing

Additional skills, rather than tools, that might be more commonly found in the modern day are basically matched to high school subjects:

History & Geography

Math & Physics

Biology & Chemistry

Business & Accounting

Literature & Politics