What is difference between part time MBA and Executive MBA? ?

Very simple: EMBA are only open to people with a minimum work experience of 10y+ (while Booth can look at candidates with 8 years of work experience, INSEAD would not look at candidates with below than 10 and 12 is usually preferred). Please note that what matters is the level of responsibility and people going for EMBA are targeted as future C-level potential. Follow the link to know more about part time mba