WiFi
Also called Wireless Fidelity or wireless local area network(wlan)
Wi-Fi is a standard for wireless computer networking that uses radio signals in the 2.4GHz or 5.0GHz band. Computers and laptops equipped with a Wi-Fi adapter can communicate with a computer network equipped with one or more access points.
More and more devices are being equipped with Wi-Fi. Among these, of course, are tablets and smartphones. In locations where WiFi is present, devices can connect to the Internet without having to be physically connected to the local computer network.
Free WiFi
Many restaurants, cafes, coffee shops and hotel accommodations offer free Wi-Fi to their customers. Hoping to attract more customers, who then stay longer, they expect to increase their sales.
Completely free wifi, of course, does not exist. Many coffee shops require wifi users to take regular refreshments, or limit access to the wifi network to a maximum length of time, in order to prevent visitors from using the location as a free workplace, without generating revenue.
Besides restaurants, free wifi can also be found on trains, at train stations and in some stores. More and more cities are offering free wifi in the city center. The aim is to become more attractive to tourists and be able to offer them local information.
Some restaurants choose precisely not to offer wifi. There, the motto is "this is where we talk to each other. It is a fact that when entering a restaurant, many guests first check what the wifi password is.
An access point or network offered to third parties for free or for a fee is also called a hotspot.
Security
Access to a Wi-Fi network can be protected in several ways. The best known is the requirement to provide a password or security code when connecting. Until the correct password is given, the network cannot be used.
Network access can also be restricted to certain devices. This is usually controlled by applying a filter that looks at the MAC address of the device trying to connect.
Users of wifi networks should be aware that it not only provides access to the Internet, but also to other devices connected to the network. Wifi traffic can theoretically be eavesdropped on. And if security is not properly in place, other users can access personal information. When connecting to public Wi-Fi networks, it is wise to use a firewall and disable options to share files and folders within the network.
Setting up fake Wi-Fi networks in the hope that people will connect to them is becoming more common. Then displaying manipulated websites to extract important data is a form of phishing.
Location determination
Because each Wi-Fi network has its own code, which is part of the technology to connect to the network, Wi-Fi can also be used for location tracking.
Google is one of the companies widely known to actively collect location data from wifi networks. By storing the location of wifi networks, a user can then have their location determined quite accurately without having to use GPS themselves.
This is a great advantage for devices that do not have GPS, but also helps optimize the battery life of mobile devices and determine location in buildings.
