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1. An electron is a subatomic particle.
2. An antiparticle of the electron is known as the positron.
3. The mass of an electron approximately equals 1/1836 that of the proton.
4. The quantum mechanical properties of the electron include an intrinsic angular momentum (spin) of a half-integer value.
5. Similar to all elementary particles, electrons exhibit properties of both particles and waves.

This text is adapted from a Wikipedia article Electron. This text is licensed under the Creative Commons Attribution-Share-Alike License 3.0.