online MBA

Online MBA is a distance learning program that gives students an opportunity to take up MBA programs via e-mail and the internet. Through an online MBA program, students can study from home and at their own speed. Professionals can enjoy flexible timings with an online MBA and can easily balance work and study.
An online MBA prepares individuals to take up professional and leadership roles in domestic, international and government corporations, after graduation. As many online MBA aspirants are working professionals and executives, these programs are structured to prepare students to face the business world. Thus, online MBA programs are in sync with today's working world.
Eligibility requirements:
Aspirants need a graduate degree to pursue Online MBA programs.
You can refer the article for more details:
https://www.shiksha.com/online-mba-programs-article-4549-1

The difference as the name suggests is in the mode of study, both are designed for different sections of people and both are relevant looking at the cause for which MBA is being done.
Regular courses are classroom session courses where students have to attend classes, this is nothing but full-time MBA which requires your complete commitment for two years. This is the most preferred by recruiters and organisations.
Distance/ correspondence courses are more about self-study where the study material is sent to the student and they have to understand and learn it on their own. The main advantage of this is fees is low as compared to executive and full-time. In distance MBA, you'll have classes once or twice during the weekends, and you'll have exams twice a year.