The Chinese New Year falls on a different day each year, around the end of January or middle of February. In 2013 it will fall on 10 February (you can see a full calendar for different years here) bringing in the new Year of the Snake.
In many countries it will be a public holiday, with some countries, including China itself, giving several days off. The celebration itself is usually known as the Spring Festival. The celebrations are spectacular with fireworks, elaborate costumes and organised events as well as special traditional foods and ceremonies.
This festival has become popular in other countries outside Asia; in fact, outside Asia the largest Chinese New Year celebration in the world is held in London. This year on 10 Feb there will be parades and other public spectacles, covering many areas of London but based in Chinatown. The London Spring Festival is becoming more famous every year and many tourists come especially to see it.