Rahu and Ketu are shadowy planets (i.e., chhayagrahas). Their nature depends very much upon the planets associated and aspecting them. They also represent the lord of the signs in which they are placed. Rahu is called Dragon's Head. Rahu is said to resemble Saturn in certain respects. Imprisonment, drowning, diseases, are denoted by Rahu.
Rahu denotes hunting, low jobs, service, degraded acts, exile, theft, magic, inventions, litigations, violence, accidents etc.
Rahu is a cruel planet, so it represents cruel acts and cruel nature. Like Saturn it indicates laziness and slow performance of duties.
Both the nodes represent people of low caste, evil people,outcastes and wicked people.