In science you will have learned about electromagnetic waves.

Microwaves and radio waves are frequently used to transmit data. This involves converting the binary data into an electromagnetic wave using a specific protocol.

Wi-Fi and Bluetooth are examples of the protocols that govern the conversion of data.

WLANs are Wireless Local Area Networks.

You probably have a WLAN at home.

If you use Wi-Fi to connect your devices, that’s a WLAN.

In a WLAN, there will be a wireless access point (WAP) which sends and receives wireless transmissions to and from the other devices.

A WAP is usually part of a box you call the broadband router.

The router will be connected (usually wired) to an internet access point in order to connect the WLAN to the internet.

Wired networks may be more difficult to install because every device needs a dedicated cable. 

Wired

Wireless

Wireless networks may save cabling costs because not every device needs a dedicated cable. 

It may be more difficult to diagnose a problem with a wired network because all the cabling may need inspection.

Cables still need to be installed in ceilings and floors to get from the wireless access point to a switch. Wireless access points must also be bought. 

Machines cannot move around because they’re limited to the area covered by the actual physical cable. 

Client machines can move around easily because there is no dedicated cable. 

Wired networks can provide transmission over longer distances than wireless networks because the copper media is more effective.

Quality may be lost because of walls, floors, or other barriers between the device and the wireless access point. 

Wired networks may need repeaters or boosters to cover distances greater than 100 meters because the signal degrades.

Repeaters and boosters may be required because a wireless signal has a very limited range. 

A wired network is less susceptible to interference from outside sources than a wireless network because the cables themselves have layers of coverings to protect them.

Wireless networks are susceptible to interference from other wireless networks or devices because the radio waves can collide with each other.

An Unshielded Twisted Pair (UTP) is susceptible to interference from the wires inside the cables, but this is very small.

A wireless network’s performance may slow down because too many users are trying to share the same radio wave frequency.

Wired networks are usually more reliable than wireless networks because they are less susceptible to interference.

A wireless connection may drop completely or the connection may be disconnecting and reconnecting frequently because the connection is unstable for some reason.

A wired network is more secure because it is more difficult (but not impossible), to tap into actual physical cables than it is to tap into radio waves.

A wireless connection is susceptible to being intercepted because the radio waves are freely moving through the air.

Wi-Fi is not the only common wireless data transmission technology.

You will probably have experienced other connection types including:

And less commonly, if you have a digital personal assistant device such as Alexa, a communication technology called Zigbee.

Energy consumption is not high when compared to other household appliances, but it is considerably higher than low-power Wi-Fi alternatives. 

Small home and business networks. Some cities are providing Wi-Fi access for residents and visitors. 

Low power consumption, which can be provided by lithium battery cells.

Exchanging data between fixed and mobile devices over short distances, such as between a PC and a keyboard.

Bluetooth Low Energy is aimed at the personal market, like fitness devices.

Uses electromagnetic fields to automatically identify and track tags attached to objects. An RFID tag consists of a tiny radio receiver and transmitter. When triggered by an electromagnetic interrogation pulse from a nearby RFID reader device, the tag transmits digital data back to the reader.

Passive tags need no energy source, except that generated by the reader.

Active tags need a small battery.

Retail - to secure goods in outlets.

Transportation - to locate goods during movement.

Passports - to hold identification information.

Animal implants - to identify ownership or medical needs. 

A standard for wireless communication for personal area networks over very limited distances.

Low-powered applications requiring no more than a long-life battery.

Home automation, medical device data collection, personal area networks, and Internet of Things.