A break in the rain shortly before Round 7 caused the field to make last-minute changes to slick tyres.
As the track began to dry out, Webber was the first to pit for slick tyres and immediately set quick sector times.
The rain then stopped and drivers began coming in for slick tyres as the track began to dry.
Sometimes an intermediate is a slick tyre with grooves cut into it.
They usually use racing slick tyres for bitumen and concrete surfaces.
Between laps 39 and 42 there was yet another round of pit stops, this time onto slick tyres.
Holdsworth took on slick tyres in his pit stop and subsequently crashed into the turn 8 wall.
Boards are often modified with slick tyres for this purpose.
All of the cars had been on slick tyres so stopping the race was the only option.
This was the first Formula One race in which slick tyres were used.