Qualifying (Quali) is a one-hour session used to determine pole position and the order the cars will line up behind... There's more... consists of three parts referred to as Q1, Q2 and Q3.
All 20 drivers start Q1 but only 15 progress to Q2. Places 16 – 20 are the Elimination Zone with drivers finishing in these places eliminated from the next session.
And then in Q2, 15 drivers start and only 10 progress to Q1. For Q2, the Elimination Zone is placed 11 – 15.
There is no Elimination zone for Q3 as everyone has been To be classified is the formal result as recorded by the FIA. Official places are recorded for qualifying and finishing.... There's more... at the end of that session.