There is the “ordinary” Magisterium - the Bishops of the worldwide teaching in union with the Pope. An example of this type of teaching was recently recognized by Blessed John Paul the Great regarding the Church’s inability to ordain women to priestly orders. Although this recognition came from the Pope, it was not taught by his singular authority, but by the authority of the Bishops around the world. JP2 was just the messenger.
Then there’s the “extraordinary” (ie, not ordinary) Magisterium. There are two types of this exercise of authority - an Ecumenical Council and a Papal ex Cathedra teaching. The Council of Trent and the teaching about the Immaculate Conception are examples of these types of authority. Although these forms of authority are not considered the ordinary forms, they are the ones that most people think of because they are the ones that are most clearly (and narrowly) defined.
Both ordinary and extraordinary teaching are equally binding upon all Catholics, but neither teaching is automatically regarded as infallible - both may be infallible, but are not automatically infallible.