For people:
* Grand: This is the most common and general way to say "tall."
* Haut: This is also used for people, but it can be considered more formal or literary.
For objects:
* Grand: This is used for objects as well, especially for things that are tall and impressive.
* Haut: This is also used for objects, but it can be more specific to height as a measurement.
Examples:
* Il est grand. (He is tall.)
* Elle est haute. (She is tall.)
* C'est un grand arbre. (It is a tall tree.)
* La maison est haute. (The house is tall.)
Remember that the choice of "grand" or "haut" can sometimes depend on the specific situation and the desired nuance.