Taekwondo is a modern martial art, characterized by it's fast, high and spinning kicks. There are multiple interpretations of the name taekwondo. Taekwondo is often translated as 'the way of hand and foot'. My definition of the name Taekwondo is

Tae='to strike or block with the foot' or 'to kick', it also means 'jump'
K'won='Fist', 'to strike or block with hand'
Do='The way of' or 'art'.
Put this together and Taekwondo means: "The art of Kicking and Punching" or "The art of unarmed combat". The sport has been founded in Korea and is one of the popular modern martial arts.

Disciplinces of taekwondo
Taekwondo has four disciplinces which are explained in a seperate page/chapter of this site. The four displinces are:

Patterns
Sparring
Self-defence
Breaktest
It is the combination of these four disciplines that makes the art called taekwondo.

Objectives of Taekwondo
to develop an appreciation for Taekwondo as a sport and as an art
to achieve physical fitness through positive participation
to improve mental discipline and emotional equanimity
to learn self-defense skills
to develop a sense of responsibility for one self and others.
Taekwondo for kids

Taekwondo has no age limits and is a very good sport for children. They learn fast reactions through games, learn to respect others and learn to know their abilities and disabilities. Competition rules are a bit different for children then they are for adults. Although children wear full body protection (preferably thicker than the protection for adults) only kicks and punches to the body are allowed, no kicks to the head.

Is Taekwondo dangerous?
Although WTF Taekwondo is a full contact sport where it is allowed to kick to the head (throwing punches to the head are not allowed), it is not very dangerous to practise Taekwondo. During training, there is no need to actually win. During competition, full protection is used to protect the competitors.

To avoid head injuries, a competitor is not allowed to participate in a competition for three months (this seems to vary) if one was knocked out by a kick to the head. If the same incident happens again after these three months, you're not allowed to participate for half a year. Another K.O. to the head after this half year period results in a permanent exclusion of competitions.

ITF Taekwondo is so-called semi-contact. It is not allowed to attack the head with full force. However, it is allowed to throw punches to the head, by using the so-called "killing-blow", stop just an inch before the target. To avoid injuries, ITF uses gloves at sparring-competition