Keyboards & Command Line Interfaces: Crash Course Computer Science #22

New Section

In this section, Carrie Anne introduces the topic of human-computer interaction and discusses the evolution of input and output devices.

Human-Computer Interaction

• Human-Computer Interaction (HCI) is a field of study that focuses on the interfaces between humans and computers.

• Early computing devices used physical controls like gears, knobs, and switches for inputs and outputs.

• Mechanical controls and patch wires were used in early electronic computers.

• Punch cards and magnetic tape replaced mechanical inputs in the 1950s. Paper printouts were still used for output.

• Computer input during this era was designed to be simple for computers to read, not necessarily user-friendly.

Evolution of Human Input

• Early computers had a basic notion of human input but didn't respond interactively to users. Inputs were fed in at the same time as the program.

• Smaller-scale computers allowed for human-in-the-loop interactions, while larger computers supported multitasking and time-sharing systems. Keyboards became a common input mechanism borrowed from typing machines.

• Christopher Latham Sholes invented the modern typewriter in 1868, which adopted the QWERTY keyboard layout that is still widely used today. Alternative layouts have been proposed but faced switching barriers due to people's investment in learning QWERTY.

Conclusion

Human-computer interaction has evolved over time, from physical controls to punch cards to keyboards as input devices. The QWERTY keyboard layout remains dominant despite alternative proposals due to switching barriers and people's familiarity with it.

Timestamps are provided where available to help locate specific parts of the video for further study.

New Section

This section discusses the history of touch-typing and the introduction of ten-finger, touch-typing.

Touch-Typing and Typewriters

• In 1888, Frank Edward McGurrin won a typing-speed contest, popularizing ten-finger, touch-typing.

• Professional typists achieved speeds upwards of 100 words per minute with touch-typing.

• Early computers adapted teletype machines, which were used for telegraphs, as a typing interface.

New Section

This section explains how teletype machines were used as computer interfaces.

Teletype Machines for Computer Use

• Teletype machines were electromechanically-augmented typewriters that could send and receive text over telegraph lines.

• These machines allowed two humans to type to one another over long distances.

• Teletype machines were easily adapted for computer use in the 1960s and 70s.

New Section

This section discusses the transition from teletype machines to screen-based terminals.

Transition to Screen-Based Terminals

• Televisions became more affordable and improved in quality by the 1970s.

• Electromechanical teletype machines were replaced with screen-based terminals.

• The existing text-only teletype protocol was recycled for these terminals.

New Section

This section explains command line interfaces on teletype machines and their prevalence until the 1980s.

Command Line Interfaces

• Command line interfaces (CLI) on teletype machines involved users typing commands and receiving responses from the computer.

• CLI remained prevalent until around the 1980s as the primary form of human-computer interaction.

• Users could type various commands, such as "ls" to list files in the current directory.

New Section

This section explores additional commands and functionalities of command line interfaces.

More Commands in CLI

• The "cat" command was used to display the contents of a file.

• The "finger" command provided information about other users on a network.

• Electromechanical teletype machines were widely used until the 1970s.

New Section

This section discusses the transition from electromechanical teletype machines to screen-based terminals.

Transition to Screen-Based Terminals

• By 1970, it became economically viable to replace electromechanical teletype machines with screen-based terminals.

• Screens offered better resolution and flexibility compared to paper-based teletype machines.

• The protocol for text-only teletype machines was reused for screen-based terminals called "terminals."

New Section

This section highlights the advantages of screen-based terminals over command line interfaces.

Advantages of Screen-Based Terminals

• Screens allowed users to delete mistakes and offered faster and more flexible interactions.

• By the end of the 1970s, screens became standard for computer interfaces.

• Command line interfaces still had interesting applications, such as early interactive text-based computer games like Zork.

New Section

This section introduces early interactive text-based computer games and their role in human-computer interaction.

Early Interactive Text-Based Games

• Early interactive text-based computer games, like Zork (created in 1977), engaged players' imaginations through textual descriptions.

• Players typed commands to interact with objects and navigate within the game world.

• These text adventure games later evolved into multiplayer MUDs (Multi-User Dungeons) and paved the way for graphical MMORPGs.

New Section

This section demonstrates how to interact with a command line interface on a screen-based terminal.

Interacting with Command Line Interface

• Users can use commands like "ls" to list files in the current directory.

• The "cd" command allows users to change directories.

• Running programs on the command line takes over the interface until halted or quit.

New Section

This section showcases an example of an early interactive text-based game called "Colossal Cave Adventure."

Playing "Colossal Cave Adventure"

• "Colossal Cave Adventure" was developed by Will Crowther in 1976.

• Players could type commands to move, interact with objects, and progress through the game.

• The program acted as a narrator, describing locations and outcomes of actions.

New Section

This section mentions the transition from text adventure games to multiplayer MUDs.

Transition to Multiplayer Text-Based Games

• Text adventure games later evolved into multiplayer MUDs (Multi-User Dungeons).

• MUDs served as precursors to modern graphical MMORPGs (massive, multiplayer online role-playing games).

Timestamps are provided for each section.

New Section

This section discusses the command line interface and its relevance in computing today.

Command Line Interface

• The command line interface is available on Windows, macOS, and Linux operating systems.

• To access the command line interface on Windows, type "cmd" in the search bar. On Mac, search for Terminal.

• Installing a copy of Zork allows users to experience early advancements in computing through the command line interface.

• These early advancements still have an impact on computing today.

The language used in this section is English.