Kumar Patel (portrayed by Kal Penn) is an Indian-American who lives in New Jersey with his best friend Harold Lee.
Kumar is an Indian-American school graduate. He has been smoking marijuana ever since his girlfriend, Vanessa, got him to smoke it in college, which transformed him from an uptight geek to a free-spirited, immature, outgoing, rebellious, laid-back stoner. Kumar is remarkably intelligent and knows how to perform complex surgical procedures, as he exemplified in Harold & Kumar Go To White Castle where he operated on a gunshot victim. His medical school interviewer, Dr. Willoughby, noted that Kumar did not make one mistake on his MCAT Tests and was shocked to see that Kumar would turn down the opportunity to attend the school.
While his brother and father pressure him to become a doctor, Kumar does not want to become one because he is lazy and hates doing work, to the point that he would rather live in poverty. In A Very Harold & Kumar Christmas, Kumar has become very poor and remained unemployed for 6 years. This made him lose Vanessa because Kumar's unemployment status meant that he couldn't afford to take care of Vanessa's child. He came back at the end to tell Vanessa he will go get a job to become a doctor to provide for their future child.