Electron

The electron was discovered in 1897 by the British physicist J. J. Thomson at the Cavendish Laboratory in Cambridge. Thomson was studying cathode rays, the glowing streams produced in evacuated glass tubes, and by deflecting them with electric and magnetic fields he showed that they consist of negatively charged particles much lighter than any atom, around two thousand times lighter than hydrogen. He called them corpuscles, and the name electron, which had been proposed earlier for the unit of charge, came into use later. The discovery showed that atoms are not indivisible and led to new models of atomic structure. Thomson received the Nobel Prize in Physics in 1906, and electrons are fundamental to chemistry, electricity and electronics.

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