In this perfectly timed photograph by Jamey Price entitled Poetry in Motion, we see the Marussia F1 Team doing a practice pit stop with Max Chilton during F1 pre-season testing at Barcelona.

There are tons of fascinating details about pit stops and the pit crew on Wikipedia. For example:

In Formula One, mid-race refuelling has been banned since 2010, and cars make pit stops with the primary purpose of changing tires. Teams sometimes also make adjustments to the front and rear wings and perform minor repairs, most commonly replacing the nose and front wing assembly.
 
Pit strategies generally call for between two and four scheduled stops, depending on the circuit. The drives between pit stops are commonly known as ‘stints’.
 
When the car is approximately one lap away from making its stop, the team’s pit crew will set up fresh tires and all needed pit equipment. Because of the overhead pneumatic rig, the team may have all pit mechanics in position prior to the car’s arrival, with the exception of the rear jack man.
 
Formula One rules limit teams to a single pit crew for the mandatory two cars entered. Therefore, teams must stagger their pit schedules so that only one of their two cars is in the pits at any given time. [Source]