Is it used in practice?
Well, that circuit in isolation only warms up a resistor, a capacitor, a diode and an inductor. So, no, that wouldn't be useful for anything. But:
What is it called?
That is a switch-mode power supply! I'm a bit surprised you're not finding this in your lecture notes, but the schematic you show is very similar to the picture on Wikipedia's Boost Converter page. So yes, that is a Boost Converter. Your Load is connected in parallel to the capacitor – the capacitor has the job of stabilizing the output voltage.
If so, how does one operate the switch and what kind of switch is it?
Depends! You can actually even manually operate a manual switch and build a Boost converter :) But that's definitely more of a fun educational-type circuit than anything useful.
Usually, these switches are made of transistors. What kind of transistor (or transistor-based switch module) depends on the actual application – you'll find NPN BJTs, N-channel MOSFETs, optically triggered devices, IGBTs, and so on, for different voltages, currents, temperature environment.
How that transistor is then operated depends on the transistor.
In real-world applications, you'll often find ICs dedicated to the job of controlling the transistor so that the voltage at the output is just right – but that's out of scope for a lecture on basic power systems, so it doesn't matter here.