Conference:
A formal prearranged meeting of people with a shared interest at which there is a group of talks from specialists on a particular subject with a target audience.
Activities held in a conference include sessions, poster presentations, networking events.
A Symposium:
A formal gathering of a number of experts in an academic setting at which papers are presented by specialists on particular subjects and discussed with a view to making recommendations concerning the problems under discussion.
A Congress:
A typically regular meeting of highly qualified delegates highlighting the achievements, notable results in a particular field of study through a series of invited talks.
A Seminar:
A lecture or presentation, educational in nature, either presented at a university or offered by a commercial or professional organization.
A Workshop:
Workshops include all the elements of seminars, but with the largest portion being emphasized on “hand-on-practice” or laboratory work.