What is Unique visitor?

A unique visitor (UV) is a person who visits a website at least once during a specified period. Usually, day, week, month, or year.

For example, if someone goes on your site every day for a month, they would count as one unique visitor. Same as someone who visited your site once.

Measuring unique visitors is essential. For example, your total website traffic is 100K a month. It could be all unique visitors or 10 thousand people visiting your site 10 times a month. So UV metric accurately shows how often people visit your site.