Formula 1 is back, with the official three-day pre-season test kicking off overnight in Bahrain.
All 10 teams and 20 drivers will be on track at some point during the testing session, as preparations for the season's opening race in Melbourne kicks into overdrive.
Those who watched any of the action from Bahrain may have noticed some of the weird and wonderful innovations that teams use to obtain data.
Two of the most prominent quirks during any pre-season test are the "flow-vis paint" and the "aero rakes".
Most cars at some point will use one or both of these innovations as they get to grips with their 2025 challengers.
While they may look odd, the innovation and science behind the paint and the rakes are vital for every team.
Simple in application, but critical to teams, the flow-vis paint is an important tool used to assess how air is moving over its cars.
In a 2023 article for F1.com, former Ferrari and Williams engineer Rob Smedley explained that the bright paint is mixed with a light oil.
As the car moves around the track, teams can monitor airflow patterns by observing how the oil evaporates and the paint dries, providing a clear visual of the aerodynamics.
"When we then analyse that — we're usually looking for things like separation, as in where the flow's separating and we're not getting decent flow structures across the surfaces of the car," Smedley said.
"That can then tell the aerodynamicists a lot about what's going on upstream of that, and hopefully that helps them to rectify certain problems on the car."
Then there are the aero rakes — a scaffolding structure that is attached to the car.
These rakes are covered in sensors that are able to measure the airflow that comes off the body of an F1 car.
This data is then sent back in real-time to the team.
Teams will run with these rakes at times during the testing sessions, as they determine how the car performs with different aerodynamic set-ups.
Some of the rakes will be obvious to see, sticking out from the side of the car. But other, smaller rakes, most notable around the front and rear axles, may be less obvious to identify.
Flow-vis and aero rakes are the two most prominent terms used during pre-season testing.
However, there are other terms which may be new to an F1 fan:
Sand bagging: This is when teams deliberately hide their true potential. They may run with a heavy fuel load, or drive with a less-powerful engine setting.
Glory run: This is the opposite to sand bagging. A glory run is when a driver goes out, attempting to set the quickest lap possible. Sometimes the fastest times in pre-season testing belong to team expected to be low on the grid. It could me those teams have improved, or they have decided to go flat-out and give themselves a little confidence boost ahead of the new season.
Installation lap: When a car comes from the garage at the start of a session it will travel around the circuit at a steady pace, before returning to the pit lane. This lap ensures basic components of the car, like the acceleration and brake pedal, are working.
All teams have two more days of testing before returning to their factories and preparing for the start of the season.
The 2025 F1 season will begin in Melbourne at the Australian Grand Prix, held from March 14-16.
