DRS in F1 is a drag reduction system, where a driver can push a button to reduce drag and overtake the competitor. It reduces drag by removing the rear wing drag. This can be performed only when the driver is within 1 sec of another driver.
A slot opens when the competitor’s car is within 1 sec and drivers can gain straight-line speed and overtake the competitor. This was introduced in 2011 and sometimes DRS is criticized since it takes away the skill of maneuvering during overtake.
With drivers using the dirty air effect while racing closely behind another car, people hoped DRS would be gone. However, with rules being revised in 2022, DRS is still very much in use.