That will depend on the person you ask and the school they attend.
Taekwondo, as it was originally developed over the decades is a martial art.
Today many of the schools focus on the sport aspect of it, with competitions being the focus. These have moved the art more away from the martial art and more into the sport, concentrating on how to win the competitions and earn points than how to actually fight.
tae kwon doA+
Karate.
Tae Kwon Do
a grandmaster of the art and extremly dangerous
Tang soo do Hapkido Tae Kwon Do
Tae kwon do can be considered both a hobby and a martial art. Many people practice tae kwon do for enjoyment, fitness, and self-defense, making it a popular hobby for individuals of all ages. However, it also involves disciplined training and a structured curriculum, distinguishing it as a martial art as well.
Tae Kwon Do is a Korean martial art. Krav Maga is an Israeli martial art. Both involve the use of kicks and punches, but the philosophies are different (as is their history).
"Tae kwon do" (also "taekwondo") is a type of Oriental martial art that originated in Korea. It is also the "national sport" of South Korea.
Yes, Tae Kwon Do should be capitalized as it is a proper noun referring to a specific martial art.
The martial art may be spelled as one word taekwondo, or separately as tae kwon do.
You would kill him. All dead opponents are considered defeated. However, taekwondo is a martial art and a sport. It has no "deathblows."
In my experience, I found Tae Kwon Do to be a more advanced and proper martial art than Karate.