The red-striped yellow flag indicates a potential traction hazard.

This flag is shown at the discretion of the marshals manning the station. When shown at a corner station, drivers are prohibited from passing until either the hazard or the next flag station displaying a green flag (signifying the end of a cautionary section) is passed. This informs the driver that there may be marshals on the track and to prepare to stop, if necessary.

Two flags waved simultaneously denotes a hazard that wholly or partly blocks the racing surface.

A single waved flag denotes a hazard on the racing surface itself.A single stationary flag denotes a hazard off the course.The solid yellow flag, or caution flag, universally requires drivers to slow down due to a hazard on the track. When shown at a corner station, a green flag may indicate the end of a local yellow-flag zone. If the session is not under caution or delayed, it is said to be under green-flag conditions, though the flag is not actually displayed. During a session, it is displayed at the end of a caution period or a temporary delay to indicate that the session is restarting. The solid green flag is usually displayed by the starter to indicate the start of a session. In addition, the green, yellow, and red flags described below may be augmented or replaced by lights at various points around the track. Status flags are used to inform all drivers of the general status of the course during a session. Instructions specific to the use of flags during a Track Day will be in blue.

On road courses, track marshals are also stationed at observation posts (corner stations) along the course in order to communicate both local and course-wide conditions to drivers. Typically, the starter, sometimes the grand marshal of a race, waves the flags atop a flag stand near the start/finish line. Track flags are traditionally used in auto racing and similar motorsports to indicate track condition and to communicate important messages to drivers.

Download blue and yellow flag in racing