Formula One teams aren't the only ones partaking in pre-season testing this weekend.
Kate Walker is your guide to a team-by-team run-down of what happened on the opening day of official Formula One testing at Jerez in Spain.
McLaren and Honda know that their road to glory may be a tough one.
Ferrari leads the way after the opening day of action at Jerez.
Repsol Honda teammates get 2015 season underway ahead of Sepang test
No fireworks from new engine so far, as team logs laps with brand new MP4-30 contender.
Formula One superstars kick-off 2015 season at Jerez for pre-season testing.
McLaren programme ended early after the engineers and mechanics were unable to resolve a technical issue.
Marcus Ericsson was able to complete 73 mainly trouble-free laps.
Carlos Sainz: "I felt good in the car today, I was constantly improving, lap after lap."
There was a sense of achievement felt among the team at the end of the day.
Valtteri Bottas: "There are a lot of strengths in this car and we’ve made good progress in just one day, so I am very pleased."
The F1 W06 Hybrid ran trouble-free throughout the day
The team showed strong development throughout last season and aim to continue this as the regulations show minimal changes for the new season ahead.