If you look at the top of your phone，you'll usually see a little symbol that says 3G or 4G. The "G" stands for the "generation（代）" of your mobile network. But the symbols will become things of the past after 5G networks fully arrive. Shanghai became the first city in China to start testing 5G networks.
About 100 times faster than 4G networks，5G lets people download and upload data（数据） faster than ever before. But 5G doesn't just bring faster mobile internet. People can use it for many other things as well. For example，5G helps to make self－driving cars safer.
5G could also be used to power the Internet of Things（IoT，物联网），that is，a large online network that connects all things and people. Fast internet speeds are the key to developing this technology.
The IoT could be used in a lot of ways. For example，with IoT，your fridge could automatically（自动地） place an order online for eggs when it finds that there are no eggs left inside.
