AP® World History: Modern · Unit 9 · Topic 9.1
From Telegraph to Internet
Communication technology compressed the time it takes a message to cross the world from months to milliseconds, but faster transmission did not automatically strip governments of the power to control information.
In 1850 a letter from London to Bombay traveled by ship and took months. The telegraph, strung along cables under oceans starting in the 1850s-1860s, cut that to hours. Telephone, then radio and television, pushed it further, and digital networks after the 1960s pushed it to nearly zero. Plot this on a chart and the trend line collapses toward flat: each new technology didn't just speed up the old one, it removed steps. The telegraph removed the physical object being carried. The internet removed the need for any single continuous line at all.
Here's the mechanism behind that last leap. When you send a message online, it doesn't travel as one piece. It gets broken into small data packets, each stamped with a destination address. Each packet gets routed independently, hopping through routers, servers, and undersea fiber-optic cables, often by different paths, before arriving and getting reassembled in the right order at the destination. This packet-switching design, built for the internet starting in the 1960s-70s and opened to ordinary users in the 1990s, is why no dedicated wire has to run the whole distance for your one message, and why internet use exploded from a handful of research networks to billions of users worldwide.
This technology is the plumbing underneath every other part of globalization: instant financial transactions, global supply chains, pandemics tracked in real time, culture spreading through shared video and music. It also raises the question of control. Just because ordinary people can broadcast instantly doesn't mean states lose power over information, which connects directly to how governments responded to this new speed.
Key terms
- Packet switching
- Breaking a message into small independently routed pieces that get reassembled at the destination, the core design of internet data transfer.
- Undersea fiber-optic cable
- A cable laid along ocean floors that carries data as light signals between continents at very high speed.
- Internet shutdown
- A deliberate government action to cut or restrict internet access in a region, often during protests or unrest.
- Censorship
- Government restriction or filtering of specific content, websites, or platforms to control what citizens can see or share.
- Telegraph
- A nineteenth-century technology that sent coded electrical signals over wires, cutting long-distance message time from months to hours.
Watch it explained
- How it worksShow me communication speed across the twentieth century as a collapsing curve.
- How it worksWalk me through how a packet of data actually gets from one continent to another.
- Worked exampleTrace the growth of internet users worldwide from 1990 to today on one chart.
- Common mistakeWhy doesn't everyone carrying a transmitter automatically mean governments lose control of information?
Check yourself
End of topic.