A label is a short name that explains what a field or control is for. It is like a name tag on a jar: it helps you know what belongs inside. On a website, a label might say “Your name” beside a field where someone types.
Labels reduce guessing and help people understand what information a form expects. They can also make a control easier to use with assistive technology, which reads page information aloud.
Put the label close to the thing it describes and use familiar words. A hint such as “name@example.com” can show a format, but it should not replace the label itself.