Tricolour

The flag of Azerbaijan representing the Azerbaijani tricolours. The stripes are horizontal (across).
The flag of France representing the French tricolours. The stripes are vertical (up and down).
The flag of the Republic of the Congo representing the Congolese tricolours. The stripes are diagonal (neither up and down nor across).

Tricolor or tricolour (meaning "three colours") is, in most cases, a flag or banner that has three colours. Tricolour is a specific type of a flag with three stripes. The stripes can be horizontal (across), vertical (up and down) or diagonal (neither up and down nor across).