Skip to main content
   

Codes

pdf download of worksheetWorksheet 1

What are codes?: Changing information from one type to another is known as encoding (or putting it into code). You can encode a message as Semaphore using flags. In a way, the human voice is encoded before we speak because the air we use changes as it passes through our vocal cords.

Telephone numbers

pdf download of worksheetWorksheet 2

The first telephones: In 1879, the first telephone exchange opened in Britain. There were only eight users with phones, and calls were connected by people called operators. They plugged and unplugged wires to join the different phone lines together. There were no telephone numbers then - people just told the operator who they wanted to call.

Numbers in code

pdf download of worksheetWorksheet 3

Morse code: Before the telephone was invented, the telegraph was used to send messages over long distances. Early telegraphs could only send pulses of electricity along a wire, not actual messages. In 1840, Samuel Morse and Alfred Vail invented a code to translate these pulses into letters and numbers, called Morse code. For example, in Morse code, the letter A is represented by a short then a long pulse of electricity. This can be written as dot dash or .

pdf download of teacher's notesCommunications Project Primary: Teacher's notes : Communicating with numbers

BT Tower activity (opened October 8, 1965)

BT Tower activity (opened October 8, 1965)BT Tower

Old exchange

Old ExchangeOld exchange map

Cost of your call activity : try and guess yourself

Cost of your call activity : try and guess yourselfCost of call
fun and games

Can you beat our games? Explode equipment to see what's inside, hear the changing sounds of telecommunications, see how telecommunications designs have changed over time or send an e-postacard.

what's on

The UK's first permanent gallery dedicated to the history of information and communication technologies opens in the new Information Age gallery at London’s Science Museum.

audio history

Take a trip down memory lane with extracts of the interviews which have been recorded as part of the Connected Earth oral history programme.

featured story

100 years of automatic switching!
In 1912 the GPO installed Britain's first automatic telephone exchange in Epsom.

Discover the early days of the telephone...