Some people may get confused at work, especially when they are told that they would have to attend a seminar or if they would need to attend a conference. Some people think that this is exactly the same thing. A conference is considered to be more formal.
It is a meeting that will be composed of different people who are all needed to provide input for the current thing that is being discussed. A seminar, on the other hand, is something that people would need to attend if they would like to learn something. For example, there are some who would attend seminars in order to know how to bake or how to cook.