vs
QUICK ANSWER
"Estoy" is a form of "estoy", a phrase which is often translated as "I'm". "Hoy" is an adverb which is often translated as "today". Learn more about the difference between "hoy" and "estoy" below.
hoy(
oy
)An adverb is a word that describes a verb, an adjective, or other adverbs (e.g., to run quickly, very tired).
2. (nowadays)
estoy
A phrase is a group of words commonly used together (e.g., once upon a time).