There are several ways to connect electronic devices to each other; cables, infrared, etc. Bluetooth technology is one of them and enabling wireless transmission of voice and/or data between devices by radio frequency.
It is a technology of radio waves at short range (2.4 GHz) whose objective is the communication between devices such as computers, smartphones, tablets, printers, headsets and other dispositives hand.
Bluetooth is called the communication protocol specifically designed for low-power devices. These devices can be classified according to their transmission power:
- Class 1: 100 mW, maximum range approximately 100 meters.
- Class 2: 2.5 mW, approximate maximum range between 5 and 10 meters.
- Class 3: 1 mW, maximum range approximately 1 meter.

We can also classify this technology by standard. All these versions have backward compatibility, ie, it allows the latest standard is compatible with all previous versions.

- Version 1.2: 1 Mbit/s
- Version 2.0 + EDR: 3 Mbit/s
- Version 3.0 + HS: 24 Mbit/s
- Version 4.0: 24 Mbit/s

The Wifi technology is a wireless communication mechanism between devices. This technology allows you to connect devices such as computers, laptops, mobile etc... to the Internet or communicate with the devices themselves.

Applications can be several, among the most common are the access points, ideal for giving and sharing a connection signal to multiple devices. It is the typical configuration of a home user.
Repeater, ideal to repeat and amplify weak signal.

The power and range between devices basically depends on the antenna and its hardware.

The wireless signals work under a unified standard regulations, the standard that is based on the IEEE 802.11. These include IEEE 802.11b, IEEE 802.11g and IEEE 802.11n working at 11 Mbit/s, 54 Mbit/s and 300 Mbit/s, respectively.
Being any device with a standardized protocol such technology can connect to another using the same technology, making it a kind of universal connection.

The wireless networks are characterized by the ease and convenience of making connections in infrastructure, since it is not necessary to perform network cable installations.
it also allows connecting a lot of devices to a single node.