The intermediate days of Passover and Sukkot (between the first and last days, which are festival days) are called “chol ha’moed.”  Passover has four chol ha’moed  days outside of Eretz Yisrael and five days in Eretz Yisrael. Sukkot has five chol ha’moed days outside of Israel and six inside Eretz Yisrael.
The restrictions that apply to the Jewish festival days generally do not apply to the chol ha’moed days (see below for exceptions).