An Internship in Finance is a professional business experience that may lead to great opportunities. An internship may result in full-time employment after graduation with the intern employer; it may provide the intern with a valuable experience making him/her more marketable to future employers; and it may allow the intern to "test drive" a specific career path (e.g. stock broker) -- do I really want to do this long term?
The internship program runs year-round. Summer positions are generally full-time, whereas most fall and spring positions are part-time. While many of the internships are compensated, few are not. And although some positions are not compensated, they may still offer a valuable experience. Be open-minded about compensation. Remember WHY you are interning -- FOR THE EXPERIENCE!!