Homonym: filter (Strainer)
A filter is a device or process that removes unwanted substances or elements from a mixture. For example, in water purification, a filter can eliminate impurities, making the water safe to drink. Filters can be physical, like a coffee filter that separates coffee grounds from liquid, or chemical, like those used in air purifiers to trap pollutants.
In technology, filters are used in various applications, such as email systems that sort out spam messages. Social media platforms also use filters to manage content, allowing users to see only what is relevant to them. Overall, filters help improve quality and efficiency in many areas.