Since liquids exert force equally in all directions we can multiply the force it gives by increasing the surface area in which we want the liquid to push against. Typically we apply this principle in a hydraulic cylinder. The greater the surface area at the end of the cylinder, the more force gets exerted on the moving piston.
Digital Multi-Meters come in two common varieties: Auto- Ranging, and Non Auto-Ranging. A non auto-ranging meter requires you to select a range of “sensitivity” for the given function you are using. For example if you want to measure resistance, you would need to select a range of up to 200 ohms, up to 20Kohms (20,000 ohms), 200Kohms, etc. An auto-ranging meter will automatically figure out the range and give you a measurement.