Do you know what 14th July stands for? It is a commemoration of the storming of the Bastille (la prise de la Bastille) which happened on 14th July 1789, during the French revolution (la révolution française). It was a very important symbol, even if only seven prisoners were freed on that day - the prison was almost empty!
Nowadays a large military parade (un défilé militaire) is held on Champs Elysées, and in the evening, most towns and villages celebrate with fireworks (les feux d'artifices).
The famous French singer Georges Brassens had a different take on the day, and in one of his most famous songs entitled Bad Reputation (La mauvaise réputation), he sings:
Le jour du 14 juillet, je reste dans mon lit douillet,
La musique qui marche au pas,
Cela ne me regarde pas.
Je ne fais pourtant de tort à personne,
En n'écoutant pas le clairon qui sonne
Mais les braves gens n'aiment pas que
L'on suive une autre route qu'eux
On the 14th of July
I keep to my cosy bed
The marching music
Holds no interest for me
Yet I don’t harm anyone
By not listening to the bugle
But good folk don’t like it when
You follow another way than theirs
If you would like to listen to the song, you can find one of many versions here, with a translation: