The most popular example of this concept was the Internet fridge, which LG brought to the world at the turn of the century. The concept was that you could surf the net while searching for the jam instead of just staring mindlessly at the fridge light. The goal of its designers was that in the future your fridge would be networked to your online shopping site so that you could have the fridge automatically order milk or food when they run low.

Although not many of us rushed out to buy an Internet fridge it did bring to the attention of the public the idea of home networking and home automation.

The ability to have a single device to manage all of your lights, appliances, heating music and video has started to gain some traction.

These systems that have been leading the charge now use the home’s existing power wiring and wireless signals to control appliances around the home.

The goal of home automation is to reduce the complexity of controlling all of the devices within a house.

For example instead of having separate controllers for security systems, shades and heating it is possible to control the system from a central point. The down side to this is that if you have a central system failure it can disrupt the operation of the entire house.

Many consumers see one of the benefits of home automation is its ability to save energy. The systems can control temperature levels through the heater and air conditioner to reduce likelihood of over heating and cooling or unnecessary use of lighting. It may also allow the system to follow the sun to regulate the natural heating and cooling of the house by opening and closing shades.

The problem often encountered with conventional home networks is that it may require re-cabling of the entire property using data cabling. This has been alleviated to some extent by systems that use the existing power cabling to deliver control signals.

The oldest and most popular of HA systems use the X10 protocol that has been applied to many household appliances.

Developed in Scotland in the 1970s the protocol uses the power line to send small bursts of control signals. The very clever part of this is that the signal does not interfere with the normal current that is using the line at the time. This is because the signal is sent while the Alternating Current (i.e. 50-60Hz) falls to zero.

At the instance that AC is going from positive to negative in an alternating fashion the control signal is passed through to the appliance. If you are controlling more than one device it is necessary to have addressing for each of the devices to avoid confusion between signals. X10 caters for this occurrence by have specific addressing for the house itself and each device which is included in the control signal.

One of the limitations of the X10 protocol is the speed at which signals are sent. In general only one part of the signal is sent every 16 milliseconds. That sounds fast but can lead to delays, especially when many devices are being controlled. To improve on these limitations, protocols such as Insteon, BACnet (larger commercial building), Zigbe (www.Control4.com) and LonWorks have been developed.

Of these methods Insteon has become very popular in households because of its interoperability with existing X10 appliances. Insteon also combines simply in line power control with wireless systems. An application of these new protocols is to have a text message sent to you if your fridge compressor fails.

From the perspective of music and video in the home the concept of media centres are gaining in popularity. A medium centre controls and stores all media contents and reduces the requirement to have DVDs, CDs and stereos. The popularity of these devices is in part due to the amount of music and video files that are now being stored in computers and portable devices such as IPods.

Another reason for the move towards a centralized media environment is the increasing number of audio and video files that are delivered from the internet to the PC. To cater for the demand of these markets vendors such as HP have developed z500 digital Entertainment centre while Microsoft have extended the range of software to include media extensions on the Windows operating systems.

The ultimate goal of home automation is something called domotics, which is essentially a building a robotic house.

It would be able to adjust lights, music and temperature to suite the requirements of different householders. It is anticipated the domotic house would recognise users by either by facial recognition technology or Radio Frequency ID tags. A very high-end example is the use voice recognition technology such as butler in a box (www.mastervoice.com), which allows for automation on voice commands.

This is a useful website which allows you to convert between different files and then emails you the results. http://www.zamzar.com/ you can convert differing audio, visual and text files.