Hi Grant,

Great question! "Beau/belle" and "joli/jolie" have different meanings, the same way "beautiful" and "pretty" do in English.

"Beau/belle" = "beautiful", so you would use it for describing something that possesses gracious, elegant, qualities of undeniable beauty.

Here are a few examples:

"Le Louvre est un beau bâtiment" (The Louvre is a beautiful building)

"La belle plage de Sète" (The beautiful beach in Sète)

"Les belles roses dans le jardin" (The beautiful roses in the garden)

"Joli/jolie" = "pretty", so you would use it for describing something that possesses visually pleasant, attractive and delicate qualities. 

Here are a few examples:

"Une jolie ferme à la campagne" (A pretty farmhouse in the countryside)

"Regarde mes jolies chaussures" (Look at my pretty shoes)

"C'est un joli service à thé" (This is a pretty tea set)

I hope this helps!