The International System of Units, SI, in use since 1946, was formally established in October 1960 by the eleventh Conférence Générale des Poids et Mesures, CGPM, with its resolution 12. In the past years, several changes have been made to the system. The 26th Conference, on 16th November 2018, adopted a revised SI, due to come into force on 20 May 2019. This revision was by far the most radical in the history of the SI. In this paper, I review the system from its origin to the present time, discuss the needs that suggested, and the conditions that allowed such an epochal change, and present the SI of the third millennium.

中文翻译：

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第三千年国际单位制

自1946年以来一直使用的国际单位制（SI）由第11届ConférenceGénéraledes Poids et Mesures CGPM及其决议12正式建立。在过去的几年中，对该系统进行了一些更改。2018年11月16日，第26届会议通过了修订后的SI，该修订版将于2019年5月20日生效。迄今为止，该修订版是SI历史上最激进的。在本文中，我将从系统的起源到现在进行回顾，讨论所提出的需求以及允许这种时代性改变的条件，并提出第三千年的SI。