That's it. Not much more detail in the question.
If the answer could include usage in a sentence, that would be helpful.
They're exactly the same word. In Arabic, the word صلاة (salah/salat) ends with what is known as a taa marbutah, which can be pronounced either as "t" (if it's in the middle of a sentence) or an "h" (if it's at the end of a sentence).