Pressure washers are powerful cleaning devices used for outdoor cleaning applications. They come in various types, including gas-powered, electric, and cordless models. Gas-powered pressure washers are ideal for heavy-duty cleaning tasks as they produce high pressure and flow rates, while electric and cordless models are suitable for lighter tasks.

Pressure washers are categorized based on their water pressure, measured in PSI (pounds per square inch) and flow rate, measured in GPM (gallons per minute). The PSI rating determines how much force the pressure washer can generate to clean surfaces, while the GPM rating determines how much water the unit can deliver to the surface being cleaned.