The essential scientific reference book for today's young scientists. Here is the ultimate guide to science and technology for the nineties and beyond. Packed with up-to-date information, The DK Science Encyclopedia explains the principles of science in a lively and exciting way. The scope of subjects covered is immense -- from atoms to lasers, acids to speedometers, and marsupials to magnets. More than 280 major entries cover key subjects such as evolution, energy, polymers, and pollution, while 1,900 subentries include biographies of great scientists and inventors, time charts detailing landmarks in science, and fact boxes on subjects of general scientific interest.