That Dam and That Luang

I took a field trip to That Dam (Taht Dahm) and That Luang. That Dam is a stupa, and That Luang is kind of like a temple. We went there to study the Lao monuments. That Luang had to be built more than 3 TIMES! That Dam used to be an ancient temple, but it is now a stupa. The meaning, "That Dam" means, "Black stupa". I am not sure what "That Luang" means.