Multics

Multics was an early operating system that implemented a single level store for data access, discarding the clear distinction between files (called segments in Multics) and process memory. The memory of a process consisted solely of segments which were mapped into its address space; to read or write to them, the process simply used normal CPU instructions, and the operating system took care of making sure that all the modifications were saved to disk. In POSIX terminology, it was as if every file was mmap()ed; howe ...

See also:

Multics, Multics - Overview, Multics - Novel ideas, Multics - Project history, Multics - Retrospective observations

Read more here: » Multics: Encyclopedia II - Multics - Novel ideas

The Defense Advanced Research Projects Agency (DARPA) is an agency of the United States Department of Defense responsible for the development of new technology for use by the military. DARPA was responsible for funding development of many technologies which have had a major impact on the world, including computer networking (starting with the ARPANET, which eventually grew into the Internet), as well as NLS, which was both the first hypertext system, and ...

Including:

• Defense Advanced Research Projects Agency - DARPA's Mission
• Defense Advanced Research Projects Agency - History
• Defense Advanced Research Projects Agency - Current Organization
• Defense Advanced Research Projects Agency - Controversy
• Defense Advanced Research Projects Agency - ARPA and DARPA in culture

Read more here: » Defense Advanced Research Projects Agency: Encyclopedia - Defense Advanced Research Projects Agency

DARPA was created as the Advanced Research Projects Agency (ARPA), by Public Law 85-325 and Department of Defense Directive 5105.41, in February 1958. Its creation was directly attributed to the launching of Sputnik and to U.S. realization that the Soviet Union had developed the capacity to rapidly exploit military technology. Additionally, the political and defense communities recognized the need for a high-level Department of Defense organization to formulate and execute R&D projects that would expand the frontiers of technology beyond ...

See also:

Defense Advanced Research Projects Agency, Defense Advanced Research Projects Agency - DARPA's Mission, Defense Advanced Research Projects Agency - History, Defense Advanced Research Projects Agency - Current Organization, Defense Advanced Research Projects Agency - Controversy, Defense Advanced Research Projects Agency - ARPA and DARPA in culture

Read more here: » Defense Advanced Research Projects Agency: Encyclopedia II - Defense Advanced Research Projects Agency - History

Computer security is a field of computer science concerned with the control of risks related to computer use. The means traditionally taken to realize this objective is to attempt to create a secure computing platform, designed so that agents (users or programs) can only perform actions that have been allowed. This involves specifying and implementing a security policy. The actions in question can be reduced to operations of access, modification and deletion. Computer security can be seen as a subfield of security engine ...

Including:

• Computer security - Computer security by design
• Computer security - Early history of security by design
• Computer security - Techniques for creating secure systems
• Computer security - Capabilities vs. ACLs
• Computer security - Other uses of the term trusted
• Computer security - Notable persons in computer security

Read more here: » Computer security: Encyclopedia - Computer security

B was the name of a programming language developed at Bell Labs. It is almost extinct, as it was replaced by the C language. It was mostly the work of Ken Thompson with contributions from Dennis Ritchie, and first appeared in 1969 or thereabouts. It was essentially the BCPL system stripped of any component that Thompson felt he could do without, in order to make it fit within the memory capacity of the minicomputers of the time. The language also included some changes made to suit Thompson's preferences (mostly along the lines of reducing t ...

Including:

• B programming language - Example

Read more here: » B programming language: Encyclopedia - B programming language

The C programming language is a standardized imperative computer programming language developed in the early 1970s by Dennis Ritchie for use on the Unix operating system. It has since spread to many other operating systems, and is one of the most widely used programming languages. C is prized for its efficiency, and is the most popular programming language for writing system software, though it is also used for writing applications. It is also commonly used in computer science education, despite not being designed for novices. Including:

• C programming language - Features
• C programming language - Overview
• C programming language - hello world example
• C programming language - Types
• C programming language - Unification of arrays and pointers
• C programming language - Data storages
• C programming language - Syntax
• C programming language - Criticism
• C programming language - Memory allocation
• C programming language - Pointers
• C programming language - Arrays
• C programming language - Variadic functions
• C programming language - Syntax
• C programming language - Maintenance problems
• C programming language - Compiler-external static-checking tools
• C programming language - History
• C programming language - Early developments
• C programming language - K&R C
• C programming language - ANSI C and ISO C
• C programming language - C99
• C programming language - Relation to C++
• C programming language - Intermediate language

Read more here: » C programming language: Encyclopedia - C programming language

A database management system (DBMS) is a computer program (or more typically, a suite of them) designed to manage a database (a large set of structured data), and run operations on the data requested by numerous clients. Typical examples of DBMS use include accounting, human resources and customer support systems. Originally found only in large organizations with the computer hardware needed to support large data sets, DBMSs have more recen ...

Including:

• Database management system - Terminology
• Database management system - History
• Database management system - Navigational DBMS
• Database management system - Relational DBMS
• Database management system - SQL DBMS
• Database management system - Object-oriented DBMS
• Database management system - Description

Read more here: » Database management system: Encyclopedia - Database management system

October 31 is the 304th day of the year (305th in leap years) in the Gregorian Calendar, with 61 days remaining, as the final day of October. October 31 - Events. October 31 is the day of halloween 475 - Romulus Augustus was proclaimed Roman Emperor. 1517 - Protestant Reformation: Martin Luther posts his 95 theses on the door of the [[Wittenberg Castle Church]]. 1587 - Leiden University Library opens its doors after its founding in 1575. ...

Including:

• October 31 - Events
• October 31 - Births
• October 31 - Deaths
• October 31 - Holidays and observances

Read more here: » October 31: Encyclopedia - October 31

From DARPA's own introduction (pdf): "DARPA is a Defense Agency with a unique role within DoD. DARPA is not tied to a specific operational mission: DARPA supplies technological options for the entire Department, and is designed to be the “technological engine” for transforming DoD. Near-term needs and requirements generally drive the Army, Navy, Marine Corps, and Air Force to focus on those needs at the expense of major change. Consequently, a large organizatio ...

See also:

Defense Advanced Research Projects Agency, Defense Advanced Research Projects Agency - DARPA's Mission, Defense Advanced Research Projects Agency - History, Defense Advanced Research Projects Agency - Current Organization, Defense Advanced Research Projects Agency - Controversy, Defense Advanced Research Projects Agency - ARPA and DARPA in culture

Read more here: » Defense Advanced Research Projects Agency: Encyclopedia II - Defense Advanced Research Projects Agency - DARPA's Mission

Telegraphy (from the Greek words tele = far and graphein = write) is the long-distance transmission of written messages without physical transport of letters, originally over wire. Radiotelegraphy or wireless telegraphy transmits messages using radio. As Albert Einstein put it, "Wire telegraph is a kind of a very, very long cat. You pull his tail in New York and his head is meowing in Los Angeles. And radio operates exactly the same way. The only difference is that there is no cat." Telegraphy includes rece ...

Including:

• Telegraphy - Optical telegraphs and smoke signals
• Telegraphy - Electrical telegraphs
• Telegraphy - Radiotelegraphy
• Telegraphy - Telegraphic improvements
• Telegraphy - Telex
• Telegraphy - TWX
• Telegraphy - Arrival of the Internet
• Telegraphy - E-mail starts to displace telegraphy
• Telegraphy - Telegraphy as a legacy system

Read more here: » Telegraphy: Encyclopedia - Telegraphy

Unix or UNIX is a computer operating system originally developed in the 1960s and 1970s by a group of AT&T Bell Labs employees including Ken Thompson, Dennis Ritchie, and Douglas McIlroy. Today's Unix systems are split into various branches, developed over time by AT&T, several other commercial vendors, as well as several non-profit organizations. Unix was designed to be portable, multi-tasking and multi-user. The Unix systems are characterized by various concepts: plain text files, command line interpreter, hier ...

Including:

• Unix - History
• Unix - 1960s and 1970s
• Unix - 1980s
• Unix - 1990s
• Unix - 2000s
• Unix - Standards
• Unix - List of Unixes
• Unix - Research Unix
• Unix - AT&T UNIX Systems & descendants
• Unix - Free Unix-like operating systems
• Unix - Impact
• Unix - Branding
• Unix - Canonical Unix Commands
• Unix - Sources

Read more here: » Unix: Encyclopedia - Unix

The Advanced Research Projects Agency Network (ARPANET) developed by ARPA of the U.S. Department of Defense was the world's first operational packet switching network, and the progenitor of the global Internet. Packet switching, now the dominant basis for both data and voice communication worldwide, was a new and important concept in data communications. Previously, data communications was based on the idea of circuit switching, as in the old typical telephone circuit, where a dedicated circuit is tied up for the duration of the call and communication is only possible with the ...

Including:

• ARPANET - Background of the ARPANET
• ARPANET - Origins of the ARPANET
• ARPANET - Creation of the ARPANET
• ARPANET - Initial ARPANET deployment
• ARPANET - Software and protocol development
• ARPANET - Applications
• ARPANET - Growth of the network
• ARPANET - Later hardware developments
• ARPANET - The ARPANET and nuclear attacks
• ARPANET - Trivia
• ARPANET - Retrospective
• ARPANET - Notes

Read more here: » ARPANET: Encyclopedia - ARPANET

In computer architecture, a bus is a subsystem that transfers data or power between computer components inside a computer or between computers. Unlike a point-to-point connection, a bus can logically connect several peripherals over the same set of wires. Each bus defines its set of connectors to physically plug devices, cards or cables together. Early computer buses were literally parallel electrical buses with multiple connections, but the term is now used for any physical arrangement that provides the same logical functional ...

Including:

• Computer bus - History
• Computer bus - Description
• Computer bus - Bus topology
• Computer bus - Examples of internal computer buses
• Computer bus - Parallel
• Computer bus - Serial
• Computer bus - Examples of external computer buses
• Computer bus - Parallel
• Computer bus - Serial
• Computer bus - Proprietary
• Computer bus - Examples of internal/external computer buses

Read more here: » Computer bus: Encyclopedia - Computer bus

1.TR.6 -- 100BaseFX -- 100BaseTX -- 100BaseT -- 100BaseVG -- 100VG-AnyLAN -- 10base2 -- 10base5 -- 10baseT -- 120 reset -- 16-bit -- 16-bit application -- 16550 UART -- 1NF -- 1TBS -- 2.PAK -- 20-Gate programming language -- 20-GATE -- 28-bit -- 2B1D -- 2B1Q -- 2D -- 2NF -- 3-tier (computing) -- 32-bit application -- 32-bit -- 320xx microprocessor -- 320xx -- 386BSD -- 386SPART.PAR -- 3Com Corporation -- 3DO -- 3D computer graphics -- 3GL -- 3NF -- 3Station -- 4.2BSD -- 404 error -- 431A -- 473L Query programming language -- 486SX -- 4GL -- 4NF -- 51forth programming language -- 56 kbit/s ...

See also:

List of computing topics, List of computing topics - 0–9, List of computing topics - A, List of computing topics - B, List of computing topics - C, List of computing topics - D, List of computing topics - E, List of computing topics - F, List of computing topics - G, List of computing topics - H, List of computing topics - I, List of computing topics - J, List of computing topics - K, List of computing topics - L, List of computing topics - M, List of computing topics - N, List of computing topics - O, List of computing topics - P, List of computing topics - Q, List of computing topics - R, List of computing topics - S, List of computing topics - T, List of computing topics - U, List of computing topics - V, List of computing topics - W, List of computing topics - X, List of computing topics - Y, List of computing topics - Z

Read more here: » List of computing topics: Encyclopedia II - List of computing topics - 0–9

History of the Internet - TCP/IP. With so many different network methods, something needed to unify them. Robert E. Kahn of ARPA and ARPANET recruited Vint Cerf of Stanford University to work with him on the problem. By 1973, they had soon worked out a fundamental reformulation, where the differences between network protocols were hidden by using a common internetwork protocol, and instead of the network being responsible for reliability, as in the ARPANET, the hosts became responsible. Cerf credits Hubert Zimmer ...

See also:

History of the Internet, History of the Internet - Before the Internet, History of the Internet - A Lack of Inter-Networking, History of the Internet - Three Terminals and an ARPA, History of the Internet - Switched Packets, History of the Internet - The networks that would lead to the Internet, History of the Internet - ARPANET, History of the Internet - X.25 and public access, History of the Internet - UUCP, History of the Internet - Merging the Networks and creating the Internet, History of the Internet - TCP/IP, History of the Internet - ARPANET to NSFNet, History of the Internet - The transition towards an Internet, History of the Internet - CERN the European Internet the link to the Pacific and beyond, History of the Internet - A digital divide, History of the Internet - Opening the network to Commerce, History of the Internet - The IETF and a standard for standards, History of the Internet - NIC InterNIC IANA and ICANN, History of the Internet - Use and Culture, History of the Internet - Email and Usenet—The growth of the text forum, History of the Internet - A world library—From Gopher to the WWW, History of the Internet - Finding what you need—The Search Engine, History of the Internet - The Dot-com Bubble

Read more here: » History of the Internet: Encyclopedia II - History of the Internet - Merging the Networks and creating the Internet

The remainder of this article discusses GNU Emacs and XEmacs, the only incarnations of Emacs that are widely used today. We will use the term "Emacs" to refer to both programs, as they have very similar features; XEmacs started as a fork of GNU Emacs, and subsequent versions have remained more or less compatible with GNU Emacs. In spite of—or perhaps because of—its venerable background, Emacs is one of the most powerful and versatile text editors in existence. It should be noted that it is primarily a text editor, not a wor ...

See also:

Emacs, Emacs - History, Emacs - Features, Emacs - Platforms, Emacs - Editing modes, Emacs - Customization, Emacs - Documentation, Emacs - Internationalization, Emacs - License, Emacs - Using Emacs, Emacs - Commands, Emacs - The minibuffer, Emacs - File management and display

Read more here: » Emacs: Encyclopedia II - Emacs - Features

Databases have been in use since the earliest days of electronic computing, but the vast majority of these were custom programs written to access custom databases. Unlike modern systems which can be applied to widely different databases and needs, these systems were tightly linked to the database in order to gain speed at the expense of flexibility. Database management system - Navigational DBMS. As computers grew in capability, this tradeoff became increasingly unnecessary and a number of general-purpose ...

See also:

Database management system, Database management system - Terminology, Database management system - History, Database management system - Navigational DBMS, Database management system - Relational DBMS, Database management system - SQL DBMS, Database management system - Object-oriented DBMS, Database management system - Description

Read more here: » Database management system: Encyclopedia II - Database management system - History

In 1950, Licklider moved from the Psycho-Acoustic Laboratory at Harvard University to MIT where he served on a committee that established MIT Lincoln Laboratory. He worked on a Cold War project known as SAGE designed to create computer-based air defense systems. In 1957 he became a Vice President at BBN, where he bought the first production PDP-1 computer and conducted the first public demonstration of time-sharing. In 1960, Licklider wrote his famous paper Man-Computer Symbiosis, which outlined the need for simpler interaction ...

See also:

J.C.R. Licklider, J.C.R. Licklider - Role in Early Computer Science Research, J.C.R. Licklider - External Resources

Read more here: » J.C.R. Licklider: Encyclopedia II - J.C.R. Licklider - Role in Early Computer Science Research

Lisp is an expression-oriented language. Unlike most other languages, no distinction is made between "expressions" and "statements"; all code and data are written as expressions. When an expression is evaluated, it produces a value (or list of values), which then can be embedded into other expressions. McCarthy's 1958 paper introduced two types of syntax: S-expressions (Symbolic Expressions, also called "sexps"), which mirror the internal representation of code and data ...

See also:

Lisp programming language, Lisp programming language - History, Lisp programming language - Syntax and Semantics, Lisp programming language - Lambda expressions, Lisp programming language - Conses and lists, Lisp programming language - Self-evaluating forms and quoting, Lisp programming language - Scope and closure, Lisp programming language - List structure of program code, Lisp programming language - Evaluation and the Read-Eval-Print Loop, Lisp programming language - Control structures, Lisp programming language - Examples, Lisp programming language - Object systems, Lisp programming language - Genealogy and variants, Lisp programming language - Major modern dialects, Lisp programming language - Historically significant dialects, Lisp programming language - Minor Dialects, Lisp programming language - Miscellaneous implementations, Lisp programming language - Related languages, Lisp programming language - Quotations

Read more here: » Lisp programming language: Encyclopedia II - Lisp programming language - Syntax and Semantics

Unix and Unix-like operating systems maintain the idea of a current working directory, that is, where one is currently positioned in the hierarchy of directories. ls when invoked without any arguments, lists the files in the current working directory. A directory that is not the current working directory can be specified and ls will list the files there. User also may specify any list of files and directories. In this case, all files and all contents of specified directories will be listed. Files whose name starts with "." are not listed, unless -a flag is specified or unless these ...

See also:

Ls, Ls - History, Ls - Behaviour, Ls - Sample usage, Ls - LC

Read more here: » Ls: Encyclopedia II - Ls - Behaviour