WiFi refers to the wireless access that is now prevalent in all the recent computer devices. Be it a mobile phone, laptop or your music system, every one of those has a wifi access. There are also WiFi portals that can be accessed, when in airports or other public locations of interest. WiFi refers to the Wireless connection based local network that is set up to a very restricted range. The WiFi technically refers to the alliance formed by the standardizing committee that cameup with and is maintaining the standard for the wireless connection based networks. Wi-Fi stands for Wireless Fidelity an represents the signal transmission mechanism over distances without physical wires.
Hotspots:
The hotspot is the one which acts as the center of connectivity for all WiFi networks. These are the ones that are announcing themselves on air, which when caught up by the devices that we use can enable the connection establishment. The WiFi accesses are restricted to very small area of coverage due to the signal transmission and reception restrictions. Usually wireless hotspots in public hotspots are stronger and configured for high power than the home networks. The WiFi hotspots can have restrictions to number of users connecting or may sometimes be accepting any number of connections. The more connections are made, the more the bandwidth is shared.
Secured Access vs Non Secured networks:
The WiFi hotspots which offer the WiFi connectivity to the other devices can have some security mechanism that is used to establish connection. There are many types of encryption, where a connecting device is required to provide one or more passwords to the hotspot router in order to establish connection. The popular encryption keys are WEP, WPA, WPA2 oriented security keys. Having a non secured access can still be implementing a security measure if the controller has restricted the devices based on the type of device or the ID of the device.
WiFi connections need not always be based on hotspots or routers. Any wireless capable computer or similar capable device can be tethered to another computer/WiFi enabled device can be turned into a hotspot or just a single point of access for another computer to connect to. This type of connection referred to as point to point access and used for personal communications or data transfer between two computers.
Obviously the advantages of the WiFi lie in the access of internet from anywhere without any wired devices required. The spectrum (wireless channel frequency) that is taken up by the WAP (Wireless Access Point – the hotspot central router ) can be varying across different countries and is not universally a standard. With increased number of access points in a single region there may be signal clashes and overlaps causing disruptions of network. Data security can be a problem even on highly secured network due to various signal interference. There are separate WiFi devices that can be attached to computers and other devices to make them WiFi enabled. This way WiFi can be accessed by even devices which do not have support built in.