Filters, also known as strainers, are tools used to separate solid particles from liquids. They work by allowing the liquid to pass through while trapping larger particles, making them essential in cooking and food preparation. For example, when making pasta, a colander is a type of strainer that helps drain the water while keeping the noodles intact. In addition to cooking, filters are also used in various industries, such as water treatment and air purification. They help ensure that the liquids and gases we use are clean and safe. Whether it's a coffee filter or a water filter, these devices play a crucial role in our daily lives.