A coffee filter is a tool used to separate coffee grounds from brewed coffee. Typically made of paper, metal, or cloth, it allows hot water to pass through while trapping the solid particles. This process results in a smooth and flavorful cup of coffee, making it an essential item for many coffee enthusiasts. Coffee filters come in various shapes and sizes to fit different brewing methods, such as drip coffee makers, French presses, and pour-over systems. They are designed to enhance the brewing process by ensuring that only liquid coffee is collected, while the grounds remain behind.