What is a rheostat? Is a rheostat just a variable resistor? How do I use a rheostat? All valid questions, here's a quick video to get you familiar with this often used device. Useful timestamps below:
00:00 - Discussions with a Salesperson
00:45 - Hello!
00:50 - The Rheostat
01:07 - Using the rheostat as a fixed resistor
01:28 - Using the rheostat as a variable resistor
01:45 - How the rheostat works as a variable resistor