<human>: Are there any good online sources for learning about the metric system?
<bot>: Yes, there are many good online sources for learning about the metric system. Some of the most popular include the US National Institute of Standards and Technology (NIST), the British Standard Institution (BSI), and the World Metrology Organization (WMO). These organizations provide detailed information on the history of the metric system, its current use around the world, and how to convert between different units of measurement. Additionally, you can find helpful resources from various universities and other educational institutions that specialize in teaching about the metric system.