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Mega-
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<h2 id="common-examples-of-usage">Common examples of usage</h2> <ul><li><a href="/facts/Megapixel/UzwBvXBV">Megapixel</a>: 1 million <a href="/facts/Pixel/UzwBvXBV">pixels</a> in a digital camera</li> <li>One megatonne of <a href="/facts/TNT_equivalent/nEQ5z8mp">TNT equivalent</a> amounts to approx. 4 <a href="/facts/Petajoule/9ndq9jD2">petajoules</a> and is the approximate energy released on igniting one million tonnes of TNT. The unit is often used in measuring the explosive power of <a href="/facts/Nuclear_weapon/QVdBcMdm">nuclear weapons</a>.</li> <li><a href="/facts/Megahertz/6Wshj5qm">Megahertz</a>: frequency of <a href="/facts/Electromagnetic_radiation/Ynx7ujCW">electromagnetic radiation</a> for radio and television broadcasting, <a href="/facts/GSM/Sw8QYaLE">GSM</a>, etc. 1 MHz = 1,000,000 <a href="/facts/Hertz/6Wshj5qm">Hz</a>.</li> <li><a href="/facts/Megabyte/RBF4XpWb">Megabyte</a>: unit of information equal to one million bytes (SI standard).</li> <li><a href="/facts/Megawatt/VK8oqRrm">Megawatt</a>: equal to one million watts of power. It is commonly used to measure the output of <a href="/facts/Power_plant/vYeVY1fD">power plants</a>, as well as the power consumption of <a href="/facts/Electric_locomotive/580UInEr">electric locomotives</a>, <a href="/facts/Data_center/DS5wJY41">data centers</a>, and other entities that heavily consume electricity.</li> <li>Megadeath: (or megacorpse) is one million human deaths, usually used in reference to projected number of deaths from a <a href="/facts/Nuclear_explosion/BtpfgcUg">nuclear explosion</a>. The term was used by scientists and thinkers who strategized likely outcomes of <a href="/facts/All-out_nuclear_warfare/mDXd7Phv">all-out nuclear warfare</a>.</li></ul> <h2 id="exponentiation">Exponentiation</h2> <p>When units occur in <a href="/facts/Exponentiation/pac6QY2g">exponentiation</a>, such as in square and cubic forms, any multiples-prefix is considered part of the unit, and thus included in the exponentiation. </p> <ul><li>1 Mm2 means one square <a href="/facts/Megametre/YzL1bHGX">megametre</a> or the size of a <a href="/facts/Square_(geometry)/JHJeMvmL">square</a> of 1000000m by 1000000m or 1012m2, and not 1000000<a href="/facts/Square_metre/u5nT9y0W">square metres</a> (106 m2).</li> <li>1 Mm3 means one cubic <a href="/facts/Megametre/YzL1bHGX">megametre</a> or the size of a <a href="/facts/Cube/65lUaAqN">cube</a> of 1000000m by 1000000m by 1000000m or 1018 m3, and not 1000000<a href="/facts/Cubic_metre/GPILKCtm">cubic metres</a> (106 m3)</li></ul> <h2 id="computing">Computing</h2> <p>In some fields of <a href="/facts/Computing/Kghtm9fX">computing</a>, <i>mega</i> may sometimes denote 1048576 (220) information units, for example, a megabyte, a megaword, but denotes 1000000 (106) units of other quantities, for example, transfer rates: 1megabit/s = 1000000<a href="/facts/Bit%2fs/ppUNMmVd">bit/s</a>. In the case of <a href="/facts/Floppy_disk/rShxfuxa">3½-inch floppy disks</a>, sizes were given in megabytes of 1000KB or 1024000 bytes.<a class="footnote-ref" id="fnref:2" href="#fn:2"><sup>2</sup></a> The prefix <i><a href="/facts/Mebi-/oM3wgJgW">mebi-</a></i> has been suggested as a prefix for 220 to avoid ambiguity. </p> <a href="/facts/Metric_prefix/Y2MzkaeL">SI prefixes</a><ul><li>v</li><li>t</li><li>e</li></ul><table><tbody><tr><th colspan="2">Prefix</th><th rowspan="2">Base 10</th><th rowspan="2"><a href="/facts/Decimal/7omfVNIM">Decimal</a></th><th rowspan="2">Adoption<a class="footnote-ref" id="fnref:3" href="#fn:3"><sup>3</sup></a></th></tr><tr><th>Name</th><th>Symbol</th></tr><tr><td>quetta</td><td>Q</td><td><a href="/facts/Orders_of_magnitude_(numbers)/uu2o1hk2">1030</a></td><td>1000000000000000000000000000000</td><td rowspan="2">2022<a class="footnote-ref" id="fnref:4" href="#fn:4"><sup>4</sup></a></td></tr><tr><td>ronna</td><td>R</td><td><a href="/facts/Orders_of_magnitude_(numbers)/uu2o1hk2">1027</a></td><td>1000000000000000000000000000</td></tr><tr><td>yotta</td><td>Y</td><td><a href="/facts/Orders_of_magnitude_(numbers)/uu2o1hk2">1024</a></td><td>1000000000000000000000000</td><td rowspan="2">1991</td></tr><tr><td>zetta</td><td>Z</td><td><a href="/facts/Orders_of_magnitude_(numbers)/uu2o1hk2">1021</a></td><td>1000000000000000000000</td></tr><tr><td>exa</td><td>E</td><td><a href="/facts/Orders_of_magnitude_(numbers)/uu2o1hk2">1018</a></td><td>1000000000000000000</td><td rowspan="2">1975<a class="footnote-ref" id="fnref:5" href="#fn:5"><sup>5</sup></a></td></tr><tr><td>peta</td><td>P</td><td><a href="/facts/Orders_of_magnitude_(numbers)/uu2o1hk2">1015</a></td><td>1000000000000000</td></tr><tr><td>tera</td><td>T</td><td><a href="/facts/Orders_of_magnitude_(numbers)/uu2o1hk2">1012</a></td><td>1000000000000</td><td rowspan="2">1960</td></tr><tr><td><a href="/facts/Giga-/vdrYKueB">giga</a></td><td>G</td><td><a href="/facts/1%2c000%2c000%2c000/Ij1fl5Q7">109</a></td><td>1000000000</td></tr><tr><td>mega</td><td>M</td><td><a href="/facts/1%2c000%2c000/RMGVIm1j">106</a></td><td>1000000</td><td>1873</td></tr><tr><td><a href="/facts/Kilo-/akxTdXyp">kilo</a></td><td>k</td><td><a href="/facts/1000_(number)/b3LRnMBK">103</a></td><td>1000</td><td rowspan="3">1795</td></tr><tr><td><a href="/facts/Hecto-/gVT7dDuw">hecto</a></td><td>h</td><td><a href="/facts/100/G6ynN9mT">102</a></td><td>100</td></tr><tr><td><a href="/facts/Deca-/IkCqeowc">deca</a></td><td>da</td><td><a href="/facts/10/pqN3l0vm">101</a></td><td>10</td></tr><tr><td>—</td><td>—</td><td><a href="/facts/1/d6SoCnze">100</a></td><td>1</td><td>—</td></tr><tr><td><a href="/facts/Deci-/umQMMcHW">deci</a></td><td>d</td><td><a href="/facts/Orders_of_magnitude_(numbers)/uu2o1hk2">10−1</a></td><td>0.1</td><td rowspan="3">1795</td></tr><tr><td><a href="/facts/Centi-/UhDg8BJG">centi</a></td><td>c</td><td><a href="/facts/Orders_of_magnitude_(numbers)/uu2o1hk2">10−2</a></td><td>0.01</td></tr><tr><td><a href="/facts/Milli-/h1TVNfuW">milli</a></td><td>m</td><td><a href="/facts/Orders_of_magnitude_(numbers)/uu2o1hk2">10−3</a></td><td>0.001</td></tr><tr><td><a href="/facts/Micro-/VXlL1EhM">micro</a></td><td>μ</td><td><a href="/facts/Orders_of_magnitude_(numbers)/uu2o1hk2">10−6</a></td><td>0.000001</td><td>1873</td></tr><tr><td><a href="/facts/Nano-/hzbPWjMK">nano</a></td><td>n</td><td><a href="/facts/Orders_of_magnitude_(numbers)/uu2o1hk2">10−9</a></td><td>0.000000001</td><td rowspan="2">1960</td></tr><tr><td>pico</td><td>p</td><td><a href="/facts/Orders_of_magnitude_(numbers)/uu2o1hk2">10−12</a></td><td>0.000000000001</td></tr><tr><td>femto</td><td>f</td><td><a href="/facts/Orders_of_magnitude_(numbers)/uu2o1hk2">10−15</a></td><td>0.000000000000001</td><td rowspan="2">1964</td></tr><tr><td>atto</td><td>a</td><td><a href="/facts/Orders_of_magnitude_(numbers)/uu2o1hk2">10−18</a></td><td>0.000000000000000001</td></tr><tr><td>zepto</td><td>z</td><td><a href="/facts/Orders_of_magnitude_(numbers)/uu2o1hk2">10−21</a></td><td>0.000000000000000000001</td><td rowspan="2">1991</td></tr><tr><td>yocto</td><td>y</td><td><a href="/facts/Orders_of_magnitude_(numbers)/uu2o1hk2">10−24</a></td><td>0.000000000000000000000001</td></tr><tr><td>ronto</td><td>r</td><td><a href="/facts/Orders_of_magnitude_(numbers)/uu2o1hk2">10−27</a></td><td>0.000000000000000000000000001</td><td rowspan="2">2022<a class="footnote-ref" id="fnref:6" href="#fn:6"><sup>6</sup></a></td></tr><tr><td>quecto</td><td>q</td><td><a href="/facts/Orders_of_magnitude_(numbers)/uu2o1hk2">10−30</a></td><td>0.000000000000000000000000000001</td></tr><tr><td colspan="5">Notes</td></tr></tbody></table> <h2 id="see-also">See also</h2> <ul><li><a href="/facts/Binary_prefix/oM3wgJgW">Binary prefix</a></li> <li><a href="/facts/Mebibyte/BNHUp9Qq">Mebibyte</a></li> <li><a href="/facts/Order_of_magnitude/cWzRP2dM">Order of magnitude</a></li> <li><a href="/facts/RKM_code/YPAFPGUm">RKM code</a></li></ul> <h2 id="external-links">External links</h2> Look up <i>mega-</i> in Wiktionary, the free dictionary. <ul><li><a href="http://www.bipm.org">BIPM website</a></li></ul> <h2 id="references">References</h2> <ol> <li id="fn:1"><p>"Oxford English Dictionary (OED Online)". www.oed.com (3rd ed.). Oxford University Press. June 2001. Retrieved 2017-09-18. Origin: A borrowing from Greek. Etymon: Greek μεγα-. ... Forming scientific and technical terms with the sense 'very large', 'comparatively large', or (esp. in Pathol.) 'abnormally large', often having correlatives beginning micro-, and sometimes also synonyms beginning macro-. <a href="http://www.oed.com/view/Entry/115861" target="_blank">http://www.oed.com/view/Entry/115861</a> <a href="#fnref:1" class="footnote-back-ref">↩</a></p></li> <li id="fn:2"><p>"Megabyte". Wolfram MathWorld. Retrieved 17 June 2024. <a href="https://mathworld.wolfram.com/Megabyte.html" target="_blank">https://mathworld.wolfram.com/Megabyte.html</a> <a href="#fnref:2" class="footnote-back-ref">↩</a></p></li> <li id="fn:3"><p>Prefixes adopted before 1960 already existed before SI. The introduction of the centimetre–gram–second system of units was in 1873. <a href="/wiki/Centimetre%E2%80%93gram%E2%80%93second_system_of_units" target="_blank">/wiki/Centimetre%E2%80%93gram%E2%80%93second_system_of_units</a> <a href="#fnref:3" class="footnote-back-ref">↩</a></p></li> <li id="fn:4"><p>"On the extension of the range of SI prefixes". 18 November 2022. Retrieved 5 February 2023. <a href="https://www.bipm.org/en/cgpm-2022/resolution-3" target="_blank">https://www.bipm.org/en/cgpm-2022/resolution-3</a> <a href="#fnref:4" class="footnote-back-ref">↩</a></p></li> <li id="fn:5"><p>"Metric (SI) Prefixes". NIST. <a href="https://www.nist.gov/pml/owm/metric-si-prefixes" target="_blank">https://www.nist.gov/pml/owm/metric-si-prefixes</a> <a href="#fnref:5" class="footnote-back-ref">↩</a></p></li> <li id="fn:6"><p>"On the extension of the range of SI prefixes". 18 November 2022. Retrieved 5 February 2023. <a href="https://www.bipm.org/en/cgpm-2022/resolution-3" target="_blank">https://www.bipm.org/en/cgpm-2022/resolution-3</a> <a href="#fnref:6" class="footnote-back-ref">↩</a></p></li> </ol>