Teletypewriters started out as a faster way to send messages long distances traveled by wires. Throughout the 1900s it eventually evolved to communicate with computers even before monitors. No longer in popularity today with the modern computer but some of the traces it left behind can still be witnessed by modern developers.
The Evolution of the TeleTypes
In 1837, the advancement of sending messages long distances evolved to include electricity. Cooke and Wheatstone obtained a patent on the telegraph system that sent currents through wires for specific letters in the message it was receiving. Samuel Morse devised the Morse code system of dots and dashes to represent letters, lowering the amount of wires needed to send messages to just one. Émile Baudot devised a system of five unit code to represent 32 possible symbols. When Donald Murray added punching cards to paper he used the Baudot Code as the encryption and included control characters like returns and line feeds.
In 1902 with the advancement of encoding, Charles Krum invented the teletypewriter funded by Joy Morton, of the Morton Salt Company. They patented their work and formed the company that would eventually be known as the Teletype Corporation. The structure of the TeleType Machine was an electro-mechanical typewriter with a built-in paper tape punching and reading machine.
The Teletype made it seamless to decipher the encoded message with the reading machine, turning it into human-readable messages. You no longer needed to be able to decipher encoded messages or get a trained telegraph interpreter to do it for you.
In 1963 the TeleType Model 33 was released with the ability to encrypt with the ASCII standard, a character encoding standard for electronic communication with computers.
Being able to communicate with a computer was an early stage of a command line interface but on hard copy paper. Just like how you would use your terminal today. A prompt character would appear, you would type in your command, and the computer would send back its response on the encrypted punched-out paper. You would feed the paper to be decrypted and typed out on your hard copy. Developers used this input-output to create some of the first types of computer-generated games, not technically video games since there was no video involved.
When Cathode Ray Tubes made it possible to display the data in an image instead of a hard copy, we no longer needed the feeding paper. “Glass Teletypes” were still expensive so most consumers kept with the old hard copy style until the prices were reasonable enough for the change. Once the price for video monitors dropped, the popularity of classic Teletypes fell out of favor. Video Terminals were faster, quieter, and did not produce any paper waste. The legacy of the teletype did not get forgotten with the old though. When the first Unix shell came out in 1971, it held onto the teletype command line by referencing it with TTY, short for teletype.
Teletype games
Before Teletypes went out of fashion, Engineers figured out how to rig up Teletypes with computer mainframes and set up an interface, they started to write code for it. Out of the many outcomes to come with interactions with a computer machine, one of the most delightful ones was the age of teletype computer games. These games took up different genres. You had adventure games, strategy games, puzzle games, etc.
The Oregon Trail, invented as an educational adventure game to teach students about the history of the Oregon Trail was first invented by three student teachers (Dan Rawitsch, Bill Heinemann, and Paul Dillenberger) in Minnesota as a Teletype Game. They had the original code for it written out in one of the punch cards that you would feed into the teletype machine. It eventually evolved to be included as the first educational game in the World Video Game Hall of Fame.
The original Lunar Lander, created a short time after man first set on the moon was a simulation game. A Massachusetts high school student named Jim Storer wrote the code with an introductory programming language called FOCAL, in under 50 lines of code.
Empire was a strategy 4x computer war game created by Peter Langston. The inspiration to similar 4x games like Civilization. Multiplayer war games are still popular today with the internet speeding things up but back in its Teletype days when the output of a move was printed out on paper, a game would normally last months or even years to finish.
Modern Terminal Games
In modern day you can still create games that can run on a “glass terminal”. Libraries like ncurses provide the functionality to write terminal games without needing to write a full GUI application. If you are not interested in writing your own terminal games there is a great selection of them you can download and play with your own command line.
There are reinventions of classic arcade games like Pacman and Tetris that use your terminal to display the image. Or ASCII-inspired games that use ASCII art to create a world for you to interact with. Games like Moon Buggy or Ninvaders use the characters on your keyboard to set up the atmosphere.
There are also games that are more inspired by the original Teletype games that were printed out on hardcopy paper. The game Secret Adventure is a text-based action game that creates a whole sci-fi world where you travel inside a shell. Once you can safely wrap your mind around the concept of escaping a shell while using a shell it is a fun way to test out your command line knowledge. Lunar Lander is also installable with the terminal, it has swapped out the text-based version that it first started out with for a visual representation of the lander, but it still holds on to the heart of the original.
With Modern technology, it is hard to imagine a world where you had to wait for a response to be read from an encoded punched-out piece of paper but it is the roots of our communication with machines and it is what leads to how we interact with technology today. The Teletype, like the early stages of computers, were chunky and loud but they were innovative. It led to the start of humans being able to get machines to take some of the load off. It was nice to learn about the start of input-output communication with computers and I hope this article taught you a bit about those early days as well.