Do you actually mean the electronics thereof, like the algorithms used to do the calculations and how the info is communicated using Bluetooth or whatever or just how, if you were presented with one instead of MDI, they work? LOL
The latter is easy.
You have a basal rate split into 24 distinct hourly rates. Each hour is split into eg 3 minute sections, and the pump delivers 3/60ths of whatever your hourly rate is, every 3 minutes. Some pumps have a minimum delivery eg 0.025 of a unit, so if that partic hour your basal rate was 0.050, you'd get two chunks of 0.025 delivered at 30 mins and 60 mins (or 0 mins and 30 mins)
So your basal is drip fed.
If you have days when you run a marathon when you need less insulin, you can have an alternative basal rate for the whole day (or longer) and just swap between your normal basal pattern (Pattern 1) and your exercise one (Pattern 2) If you is a girl and need more insulin at certain times to counteract your monthly cycle, well that could be Pattern 3. My Roche Spirit Combo gives me up to 5 different patterns I can prog to suit me. I mean, none of it is pre-set.
Boluses are kinda the same as pen delivery, except you can do extra things with that bolus such as split it, or alternatively, drip feed it. Or a mixture of that. Xunits now and the rest drip fed over the next however long. 15 minutes, 6 hours, whatever. It does that for you once you've told it to.
Pumps have summat called a Bolus Wizard, that looks at your BG, your Insulin already on Board (we say IOB or B (bolus)OB) and the amount of carbs you tell it, and works out what to bolus, which you can either tell it to deliver or manually alter before doing so. (You have previously given it info on what your I:C ratio is at various times of day, and what you want your BG to be between the hours of whatever and whatever. Like you might want to be 7.5 all through the night but 5.5 the rest of the time. Or something)
Just like MDI, it's as good as the User, Austin.
Is that enough for now? Think there's a video on the Roche website.