0 a computer, mobile phone, or a specially designed device from which people can connect to the internet by wi-fi, without having to connect to a public wi-fi point; the use of a mobile phone, etc. in such a way:
You can use a mobile Wi-Fi router to create a portable hotspot you can connect your devices to.
If you have a 4G portable hotspot you can use a 3G SIM inside.
Turn on the portable Hotspot and you will be connected to the Internet in seconds.