千百年來,人類利用各種裝置來計時和報時。目前正在使用的六十進制時間系統,大約可以追溯至公元前2000年的蘇美爾。古埃及把一天分為二個部份,每一部份再分為12個小時,並使用大型方尖碑追蹤太陽的移動。他們還發明了水鐘(water clocks)。Precinct of Amun-Re(英語:Precinct of Amun-Re) 很可能是最初使用水鐘的地方,後來在埃及以外的地方也有人使用水鐘;古希臘人就經常使用叫作clepsydrae的水鐘。約在同一時間,相信商朝已使用洩水型水鐘──漏壺;而漏壺可能早在公元前2000年,從美索不達米亞傳入。其他古代計時器包括有蠟燭鐘──在中國、日本、英格蘭,和伊拉克使用;日晷──在印度和西藏,以及歐洲一些地區廣泛使用;此外,還有沙漏,運作原理和水鐘一樣。
1921年,華持·加廸(英語:Walter G. Cady)(Walter G. Cady)製造第一個石英晶體諧振器。沃倫·馬利遜(Warren Marrison J. W. Horton)和JW.霍頓(J. W. Horton)於1927年,在加拿大的貝爾實驗室製造首個石英鐘[31][32]。之後幾十年,因為由真空管組成的石英鐘笨重,它只能設置於實驗室中。
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