My Bosch cooktop freaks out with a drop of water; it's really annoying.
AFAIK, touchscreens basically work by detecting the water in your fingers (fingers, like most of the body, contain lotsa water); so actual water can triggger them.
However, water will likely break a mechanical keyboard/switch if not dried promptly.
(Membrane keyboards are probably fine.)
Resistive touchscreens have an outer flexible panel, a sheet of invisible contacts, and an inner glass layer. When you press the outer surface the contacts in that location are physically closed and the computer registers a touch. They generally can't do multi-touch, but they do work with gloves of any type and require a firm enough press that anything bouncing, hitting, or splashing on the screen is unlikely to activate it.
The other nice thing about resistive screens is that you can tape a sacrificial piece of clear plastic over the top to protect it. Once that gets scratched or dirty, replace... and the touch function still works.
A membrane keyboard is certainly water/coolant resistant, but even if the contacts are rated for a billion presses the overlay wears out and then the whole thing is junk. Also they may not have a great tactile feel, especially for typing.
There are some rather good waterproof panel-mount keyboards available these days, either from ebay or Aliexpress. Many configurations - with/without touchpads or trackballs, stainless fronts, different key combos. The one I got recently has a stainless face and keys, but the actual tactile switches are under a continuous sheet of rubber - no water ingress. I wouldn't want to type a novel on it, but it feels quite good for a very robust keyboard.
I have Cherry mx keyboard switches on my mill control panel and have had no issues with coolant or chips damaging the switches. Unless the switch panel is horizontal (or nearly), any liquid splashing on the panel is likely to drain down before it gets to the switch contacts or mechanism. What kills mechanical keyboards is dumping a quart of sugary soda on them until the mechanical bits are submerged and they get glued in place.
The proliferation of people making a living banging away on keyboards means there's been an explosion of mechanical keyboard parts, instructions, and related stuff available for a few years to consumers:
- Sockets for Cherry mx-type switches that solder to a perf board. Meaning if a switch fails it's extremely easy to replace.
- Clear switch caps for inserting your own legends
- Multiple switch 'feel' varieties
- Aftermarket springs to stiffen up the action (even the stiffest 'stock' switch feels pretty limp compared to industrial pushbuttons)
- Vendors eager to machine/cast/print custom buttons
- Online keyboard layout generators with standardized key spacing and templates
