An electron is a subatomic particle with a negative electric charge. They join with protons and neutrons to form atoms and are kept in varying orbits around the atom by the positive charge of the nucleus. These orbits form an electron cloud which defines the size of the atom.http://science.jrank.org/pages/2374/Electron.html

The discovery of the electron is attributed to Joseph John Thomson and his experiments in 1897, which were the first to reach quantitative measurements with electrons.http://science.jrank.org/pages/2374/Electron.html Further experiments based on Thomson's findings finalized his theory for the scientific community.http://www.egglescliffe.org.uk/physics/particles/electron/electron.html The advances these discoveries had for physics research and other forms of science led to the development of technologies such as television, computers, the electron microscope, and more.http://www.aip.org/history/electron/jjhome.htm

Research on the concept of the electron was conducted as early as 1838 by Michael Faraday. He discovered that a current of electricity was created when an electric charge of several thousand volts was set between two metal electrodes in a glass tube. The existence of particles within these electric currents was determined when they were deflected in an electric field.http://science.jrank.org/pages/2374/Electron.html

It was not until J.J. Thomson's experiments in 1897 that the current definition of electrons started to form. Before his experiments, it had been believed that the atom itself was the smallest unit of matter in existence. Thomson's experiments with cathode tubes, the type of tube Faraday's experiments had pioneered, suggested that the charged particles within the cathode rays were particles smaller than atoms. He initially called these particles corpuscles.http://www.egglescliffe.org.uk/physics/particles/electron/electron.html

The term electron was not coined for the particles in Thomson's findings until 1891, when Johnstone Stoney used the term to reference the negative electrical charge he found in his own experiments with the corpuscles.http://www.egglescliffe.org.uk/physics/particles/electron/electron.html

Along with protons and neutrons, electrons are one of the subatomic particles that form atoms. Electrons have a negative electric charge, which keeps them attracted to the positive charge of the protons in the nucleus.http://www.windows2universe.org/physical_science/physics/atom_particle/electron.html Electrons are the smallest portion of an atom, being only 1/1836 times the mass of a proton or neutron.http://science.jrank.org/pages/2374/Electron.html

The orbits electrons take around the nucleus form an electron cloud, The electron cloud represents the general area where electrons will be located around an atom. It also serves as an indication of the size of the atom.http://science.jrank.org/pages/2374/Electron.html

Neutral atoms have an equal number of electrons and protons. However, it is possible for an atom to gain and lose electrons. This occurrence leaves behind an ion with a positive or negative charge, depending on how many electrons it has in relation to protons. The ion is negatively charged if there are more electrons, and positively charged if there are more protons.http://www.windows2universe.org/physical_science/physics/atom_particle/electron.html

Free electrons, which are electrons that have fallen out of orbit with their atom, can be accelerated by electric and magnetic fields. The speeds these electrons are capable of reaching can lead to particle radiation.http://www.windows2universe.org/physical_science/physics/atom_particle/particle_radiation.html The presence of free electrons and/or negatively charged ions in a material creates static electricity.http://www.school-for-champions.com/science/electricity.htm