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Robert Morris (cryptographer)
Robert H. Morris Sr. (July 25, 1932 – June 26, 2011) was an American cryptographer and computer scientist. __TOC__ Family and education Morris was born in Boston, Massachusetts. His parents were Walter W. Morris, a salesman, and Helen Kelly Morris, a homemaker. He received a bachelor's degree in mathematics from Harvard University in 1957 and a master's degree in applied mathematics from Harvard in 1958. He married Anne Farlow, and they had three children together: Robert Tappan Morris (author of the 1988 Morris worm), Meredith Morris, and Benjamin Morris. Bell Labs From 1960 until 1986, Morris was a researcher at Bell Labs and worked on Multics and later Unix. Together with Douglas McIlroy, he created M6 macro processor in FORTRAN IV, which was later ported to Unix. Using the TMG compiler-compiler, Morris, together with McIlroy, developed the early implementation of PL/I compiler called EPL for Multics project. The pair also contributed a version of runoff text-forma ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Boston
Boston (), officially the City of Boston, is the state capital and most populous city of the Commonwealth of Massachusetts, as well as the cultural and financial center of the New England region of the United States. It is the 24th- most populous city in the country. The city boundaries encompass an area of about and a population of 675,647 as of 2020. It is the seat of Suffolk County (although the county government was disbanded on July 1, 1999). The city is the economic and cultural anchor of a substantially larger metropolitan area known as Greater Boston, a metropolitan statistical area (MSA) home to a census-estimated 4.8 million people in 2016 and ranking as the tenth-largest MSA in the country. A broader combined statistical area (CSA), generally corresponding to the commuting area and including Providence, Rhode Island, is home to approximately 8.2 million people, making it the sixth most populous in the United States. Boston is one of the oldest ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mathematics
Mathematics is an area of knowledge that includes the topics of numbers, formulas and related structures, shapes and the spaces in which they are contained, and quantities and their changes. These topics are represented in modern mathematics with the major subdisciplines of number theory, algebra, geometry, and analysis, respectively. There is no general consensus among mathematicians about a common definition for their academic discipline. Most mathematical activity involves the discovery of properties of abstract objects and the use of pure reason to prove them. These objects consist of either abstractions from nature orin modern mathematicsentities that are stipulated to have certain properties, called axioms. A ''proof'' consists of a succession of applications of deductive rules to already established results. These results include previously proved theorems, axioms, andin case of abstraction from naturesome basic properties that are considered true starting points of t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Crypt (Unix)
In Unix computing, crypt or enigma is a utility program used for encryption. Due to the ease of breaking it, it is considered to be obsolete. The program is usually used as a filter, and it has traditionally been implemented using a "rotor machine" algorithm based on the Enigma machine. It is considered to be cryptographically Cryptography, or cryptology (from grc, , translit=kryptós "hidden, secret"; and ''graphein'', "to write", or '' -logia'', "study", respectively), is the practice and study of techniques for secure communication in the presence of adv ... far too weak to provide any security against brute-force attacks by modern, commodity personal computers. Some versions of Unix shipped with an even weaker version of the ''crypt(1)'' command in order to comply with Export of cryptography from the United States, contemporaneous laws and regulations that limited the exportation of cryptographic software. Some of these were simply implementations of the Ca ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dc Programming Language
dc (''desk calculator'') is a cross-platform reverse-Polish calculator which supports arbitrary-precision arithmetic. Written by Lorinda Cherry and Robert Morris at Bell Labs, it is one of the oldest Unix utilities, preceding even the invention of the C programming language. Like other utilities of that vintage, it has a powerful set of features but terse syntax. Traditionally, the bc calculator program (with infix notation) was implemented on top of dc. This article provides some examples in an attempt to give a general flavour of the language; for a complete list of commands and syntax, one should consult the man page for one's specific implementation. History dc is the oldest surviving Unix language program. When its home Bell Labs received a PDP-11, dcwritten in Bwas the first language to run on the new computer, even before an assembler. Ken Thompson has opined that dc was the very first program written on the machine. Basic operations To multiply four and five in dc (n ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Research Unix
The term "Research Unix" refers to early versions of the Unix operating system for DEC PDP-7, PDP-11, VAX and Interdata 7/32 and 8/32 computers, developed in the Bell Labs Computing Sciences Research Center (CSRC). History The term ''Research Unix'' first appeared in the Bell System Technical Journal (Vol. 57, No. 6, Pt. 2 Jul/Aug 1978) to distinguish it from other versions internal to Bell Labs (such as PWB/UNIX and MERT) whose code-base had diverged from the primary CSRC version. However, that term was little-used until Version 8 Unix, but has been retroactively applied to earlier versions as well. Prior to V8, the operating system was most commonly called simply UNIX (in caps) or the UNIX Time-Sharing System. AT&T licensed Version 5 to educational institutions, and Version 6 also to commercial sites. Schools paid $200 and others $20,000, discouraging most commercial use, but Version 6 was the most widely used version into the 1980s. Research Unix versions are often ref ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
TYPSET And RUNOFF
TYPSET is an early document editor that was used with the 1964-released RUNOFF program, one of the earliest text formatting programs to see significant use. Of two earlier print/formatting programs DITTO and TJ-2, only the latter had, and introduced, text justification; RUNOFF also added pagination. The name RUNOFF, and similar names led to other formatting program implementations. By 1982 ''Runoff'' largely became associated with Digital Equipment Corporation and Unix computers. DEC used the terms ''VAX DSR'' and ''DSR'' to refer to ''VAX DIGITAL Standard Runoff''. History CTSS The original RUNOFF type-setting program for CTSS was written by Jerome H. Saltzer circa 1964. Bob Morris and Doug McIlroy translated that from MAD to BCPL. Morris and McIlroy then moved the BCPL version to Multics when the IBM 7094 on which CTSS ran was being shut down. Multics Documentation for the Multics version of RUNOFF described it as "types out text segments in manuscript form." Other ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
PL/I
PL/I (Programming Language One, pronounced and sometimes written PL/1) is a procedural, imperative computer programming language developed and published by IBM. It is designed for scientific, engineering, business and system programming. It has been used by academic, commercial and industrial organizations since it was introduced in the 1960s, and is still used. PL/I's main domains are data processing, numerical computation, scientific computing, and system programming. It supports recursion, structured programming, linked data structure handling, fixed-point, floating-point, complex, character string handling, and bit string handling. The language syntax is English-like and suited for describing complex data formats with a wide set of functions available to verify and manipulate them. Early history In the 1950s and early 1960s, business and scientific users programmed for different computer hardware using different programming languages. Business users were moving ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
TMG (language)
In computing TMG (TransMoGrifier) is a recursive descent compiler-compiler developed by Robert M. McClure and presented in 1965. TMG ran on systems including OS/360 and early Unix. It was used to build EPL, an early version of PL/I. Douglas McIlroy ported TMG to an early version of Unix. According to Ken Thompson, McIlroy wrote TMG in TMG on a piece of paper and "decided to give his piece of paper his piece of paper," hand-compiling assembly language that he entered and assembled on Thompson's Unix system running on PDP-7. Thompson used TMG in 1970 as a tool to offer Fortran, but due to memory limitations of PDP-7 ended up creating the B programming language which was much influenced by BCPL. The recursive descent algorithm of TMG was studied formally by Alexander Birman and Jeffrey Ullman. The formal description of the algorithms was named ''TMG recognition scheme'' (or simply ''TS''). See also * Top-down parsing language * Yacc Yacc (Yet Another Compiler-Compiler) is a c ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
General-purpose Macro Processor
A general-purpose macro processor or general purpose preprocessor is a macro processor that is not tied to or integrated with a particular language or piece of software. A macro processor is a program that copies a stream of text from one place to another, making a systematic set of replacements as it does so. Macro processors are often embedded in other programs, such as assemblers and compilers. Sometimes they are standalone programs that can be used to process any kind of text. Macro processors have been used for language expansion (defining new language constructs that can be expressed in terms of existing language components), for systematic text replacements that require decision making, and for text reformatting (e.g. conditional extraction of material from an HTML The HyperText Markup Language or HTML is the standard markup language for documents designed to be displayed in a web browser. It can be assisted by technologies such as Cascading Style Sheets (CSS) ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Douglas McIlroy
Malcolm Douglas McIlroy (born 1932) is a mathematician, engineer, and programmer. As of 2019 he is an Adjunct Professor of Computer Science at Dartmouth College. McIlroy is best known for having originally proposed Unix pipelines and developed several Unix tools, such as spell, diff, sort, join, graph, speak, and tr. He was also one of the pioneering researchers of macro processors and programming language extensibility. He participated in the design of multiple influential programming languages, particularly PL/I, SNOBOL, ALTRAN, TMG and C++. His seminal work on software componentization and code reuse makes him a pioneer of component-based software engineering and software product line engineering. Biography McIlroy earned his bachelor's degree in engineering physics from Cornell University, and a Ph.D. in applied mathematics from MIT in 1959 for his thesis ''On the Solution of the Differential Equations of Conical Shells'' (advisor Eric Reissner). He taught at MIT ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
The Washington Post
''The Washington Post'' (also known as the ''Post'' and, informally, ''WaPo'') is an American daily newspaper published in Washington, D.C. It is the most widely circulated newspaper within the Washington metropolitan area and has a large national audience. Daily broadsheet editions are printed for D.C., Maryland, and Virginia. The ''Post'' was founded in 1877. In its early years, it went through several owners and struggled both financially and editorially. Financier Eugene Meyer (financier), Eugene Meyer purchased it out of bankruptcy in 1933 and revived its health and reputation, work continued by his successors Katharine Graham, Katharine and Phil Graham (Meyer's daughter and son-in-law), who bought out several rival publications. The ''Post'' 1971 printing of the Pentagon Papers helped spur opposition to the Vietnam War. Subsequently, in the best-known episode in the newspaper's history, reporters Bob Woodward and Carl Bernstein led the American press's investigation into ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
