An electron is a very small piece of matter and energy. Its symbol is e. It was discovered by J.J.Thomson in 1897.

The electron is a subatomic particle. It is believed to be an elementary particle because it cannot be broken down into anything smaller.[1] It is negatively charged,[2] and may move almost at the speed of light.[3]

Electrons take part in gravitational, electromagnetic and weak interactions.[4] The electricity that powers televisions, motors, mobile phones, and many other things is actually many electrons moving through wires or other conductors.


Electrons have the smallest electrical charge. This electrical charge equals the charge of a proton, but has the opposite sign. For this reason, electrons are attracted by the protons of atomic nuclei and usually form atoms. An electron has a mass of about 1/1836 times a proton.[5]

One way to think about the location of electrons in an atom is to imagine that they orbit at fixed distances from the nucleus. This way, electrons in an atom exist in a number of electron shells surrounding the central nucleus. Each electron shell is given a number 1, 2, 3, and so on, starting from the one closest to the nucleus (the innermost shell). Each shell can hold up to a certain maximum number of electrons. The distribution of electrons in the various shells is called electronic arrangement (or electronic form or shape). Electronic arrangement can be shown by numbering or an electron diagram. (A different way to think about the location of electrons is to use quantum mechanics to calculate their atomic orbitals.)

The Niels Bohr model of the atom. Three electron shells about a nucleus, with an electron moving from the second to the first level and releasing a photon.

The electron is one of a type of subatomic particles called leptons. The electron has a negative electric charge. The electron has another property, called spin. Its spin value is 1/2, which makes it a fermion.

While most electrons are found in atoms, others move independently in matter, or together as cathode rays in a vacuum. In some superconductors, electrons move in pairs. When electrons flow, this flow is called electricity, or an electric current.

An object can be described as 'negatively charged' if there are more electrons than protons in an object, or 'positively charged' when there are more protons than electrons. Electrons can move from one object to another when touched. They may be attracted to another object with opposite charge, or repelled when they both have the same charge. When an object is 'grounded', electrons from the charged object go into the ground, making the object neutral. This is what lightning rods ( lightning conductors ) do.

Chemical reactions

Electrons in their shells round an atom are the basis of chemical reactions. Complete outer shells, with maximum electrons, are less reactive. Outer shells with less than maximum electrons are reactive. The number of electrons in atoms is the underlying basis of the chemical periodic table.[6]


Electric charge can be directly measured with a device called an electrometer. Electric current can be directly measured with a galvanometer. The measurement given off by a galvanometer is different from the measurement given off by an electrometer. Today laboratory instruments are capable of containing and observing individual electrons.

'Seeing' an electron

In laboratory conditions, the interactions of individual electrons can be observed by means of particle detectors, which allow measurement of specific properties such as energy, spin and charge.[7] In one instance a Penning trap was used to contain a single electron for 10 months.[8] The magnetic moment of the electron was measured to a precision of eleven digits, which, in 1980, was a greater accuracy than for any other physical constant.[9]

The first video images of an electron's energy distribution were captured by a team at Lund University in Sweden, February 2008. The scientists used extremely short flashes of light, called attosecond pulses, which allowed an electron's motion to be observed for the first time.[10][11] The distribution of the electrons in solid materials can also be visualized.[12]


The antiparticle of the electron is called a positron. This is identical to the electron, but carries electrical and other charges of the opposite sign. When an electron collides with a positron, they may scatter off each other or be totally annihilated, producing a pair (or more) of gamma ray photons.

Other Languages
Afrikaans: Elektron
Alemannisch: Elektron
العربية: إلكترون
aragonés: Electrón
অসমীয়া: ইলেকট্ৰন
asturianu: Electrón
azərbaycanca: Elektron
تۆرکجه: الکترون
বাংলা: ইলেকট্রন
Bân-lâm-gú: Tiān-chú
башҡортса: Электрон
беларуская: Электрон
беларуская (тарашкевіца)‎: Электрон
български: Електрон
Boarisch: Elektron
bosanski: Elektron
brezhoneg: Elektron
català: Electró
Чӑвашла: Электрон
čeština: Elektron
Cymraeg: Electron
dansk: Elektron
Deutsch: Elektron
eesti: Elektron
Ελληνικά: Ηλεκτρόνιο
emiliàn e rumagnòl: Eletròun
English: Electron
español: Electrón
Esperanto: Elektrono
euskara: Elektroi
فارسی: الکترون
Fiji Hindi: Electron
føroyskt: Elektron
français: Électron
Frysk: Elektron
Gaeilge: Leictreon
galego: Electrón
ગુજરાતી: ઈલેક્ટ્રોન
хальмг: Электрон
한국어: 전자
հայերեն: Էլեկտրոն
हिन्दी: इलेक्ट्रॉन
hrvatski: Elektron
Ilokano: Elektron
Bahasa Indonesia: Elektron
interlingua: Electron
isiXhosa: Ii-electrons
íslenska: Rafeind
italiano: Elettrone
עברית: אלקטרון
Basa Jawa: Èlèktron
ქართული: ელექტრონი
қазақша: Электрон
Kiswahili: Elektroni
Kreyòl ayisyen: Elektwon
kurdî: Kareva
Кыргызча: Электрон
Latina: Electron
latviešu: Elektrons
Lëtzebuergesch: Elektron
lietuvių: Elektronas
Ligure: Elettron
Limburgs: Elektron
lingála: Eléktron
Lingua Franca Nova: Eletron
la .lojban.: dutydikca kantu
lumbaart: Elettron
magyar: Elektron
македонски: Електрон
മലയാളം: ഇലക്ട്രോൺ
मराठी: विजाणू
Bahasa Melayu: Elektron
Mìng-dĕ̤ng-ngṳ̄: Diêng-cṳ̄
монгол: Электрон
မြန်မာဘာသာ: အီလက်ထရွန်
Nederlands: Elektron
नेपाली: इलेक्ट्रोन
नेपाल भाषा: इलेक्ट्रोन
日本語: 電子
Nordfriisk: Elektron
norsk: Elektron
norsk nynorsk: Elektron
Novial: Elektrone
occitan: Electron
oʻzbekcha/ўзбекча: Elektron
ਪੰਜਾਬੀ: ਬਿਜਲਾਣੂ
پنجابی: الیکٹران
Patois: Ilekchran
ភាសាខ្មែរ: អេឡិចត្រុង
Piemontèis: Eletron
Plattdüütsch: Elektron
polski: Elektron
português: Elétron
Ripoarisch: Elektron
română: Electron
Runa Simi: Iliktrun
русиньскый: Електрон
русский: Электрон
संस्कृतम्: विद्युदणुः
Scots: Electron
Seeltersk: Elektron
shqip: Elektroni
sicilianu: Elettrùni
سنڌي: برقيو
slovenčina: Elektrón
slovenščina: Elektron
Soomaaliga: Elektaroon
کوردی: ئێلێکترۆن
српски / srpski: Електрон
srpskohrvatski / српскохрватски: Elektron
Basa Sunda: Éléktron
suomi: Elektroni
svenska: Elektron
Tagalog: Elektron
татарча/tatarça: Электрон
తెలుగు: ఎలక్ట్రాన్
Türkçe: Elektron
ᨅᨔ ᨕᨘᨁᨗ: Elektron
українська: Електрон
اردو: برقیہ
ئۇيغۇرچە / Uyghurche: ئېلېكترون
vèneto: Ełetron
vepsän kel’: Elektron
Tiếng Việt: Electron
Võro: Elektron
文言: 電子
Winaray: Electron
Wolof: Mbëjfepp
吴语: 电子
ייִדיש: עלעקטראן
粵語: 電子
žemaitėška: Alektruons
中文: 电子