Technology changes so quickly that new communication devices are being invented and improved all the time. Computers and mobile phones are smaller and are able to do more things. Can you imagine what Marconi would think of mobile phones today? Communication makes our modern world a small place because it allows us to talk easily with people all over the globe. In Chapter 3, you can discover how the internet and email have had a major impact on the way we communicate. This chapter looks at some of the other modern devices that we use to send and receive information and stay in touch with each other.
There are more than 100 communication satellites that are orbiting (travelling around) the Earth. They are called geostationary satellites, which means that they travel at the same speed as the Earth. The satellites receive signals from transmitter dishes and send the signals to other stations on Earth. This is how information is sent between countries around the world. See image 2
Some portable telephones are linked to satellites so that the person using the phone can make a call from anywhere in the world. Satellite phones are an important link for people who are living or working in remote areas where mobile phones do not work.
Computer chips mean that mobile phones can be used to make and receive phone calls, send text messages, take photos and movies, tell the time, and listen to the radio.
SMS stands for Short Messaging Service. This is a feature of mobile phones that lets you type messages by using the letters on your keypad. Once you have finishing writing your message, you can send it to other mobile phones. It is useful for people who want to send short messages and do not want to make a telephone call.
Video phones and video conferencing