The C programming language was devised in the early 1970s as a system implementation language for the nascent Unix operating system. Derived from the typeless language BCPL, it evolved a type structure; created on a tiny machine as a tool to improve a meager programming environment, it has become one of the dominant languages of today. This paper studies its evolution.
The EDSAC was the world's first stored-program computer to operate a regular computing service. Designed and built at Cambridge University, England, the EDSAC performed its first calculation on 6th May 1949.
Contrary to popular belief, God did not create the operating system
in six days. If He had, it would have been much better than the
ones we have now. Nonetheless, we got 'em, so we'd better learn 'em.
While some operating systems, like the love-hate Unix, have been
around since the early days of digital computing (read 1960's),
most have appeared in the late 70's to the present time, varying
from powerful multiuser OS's to little OS's that ran on 8 bit
computers in under 64K of memory. This is just the briefest portion
of operating systems, from then until now.
Silicon Valley, CA and Route 128, MA are two of the premiere technological concentrations, not only in the United States, but in the world . These are regions that since World War II have been devoted to the creation of new information technology. Comparing the two regions enables us to observe the different means by which an economic areal unit can attain success in the information revolution and indicates which strategies are most conducive to long-term success.
On New Year's Eve 1999, when we flip from 31/12/99 to 01/01/00, many computers won't know what Year 00 is and will assume either it's 1900 or nil-input.
This is an important issue that must be examined. Any company, organization, or government that doesn't take the time to look at how their systems will operate in the Year 00 is inviting disaster.
But ... most companies, organizations, and governments are doing or have already done so. The only reason to panic or worry would be if no one was doing anything about it. The issue does indeed exist; it's just not as gigantic a problem as it has been inflated to be.
The emphasis of the collection of the Computer Museum is on technical and scientific electronic computing equipment from World War II up till today. However the collection also includes tools from the pre-computer era: mechanical, electromechanical and electronic calculators, slide rules and tables. There are some word-processors and a small collection of home computers. Accounting machines, game computers and the like are beyond the scope of this museum.
Most of the machines are in working order, equipped with original system and application software and fully documented.
In 1948 the government's chief scientist initiated a government contract with Ferranti Ltd. to make a production version of the Manchester Mark 1 "to Professor Williams' specification". This was important because it established a link between the university and industry, and ensured that the power of the electronic computer would be available as quickly as possible around the U.K (and abroad).
The architecture was closely based on the Manchester Mark 1, which was effectively treated as the prototype for the commercial version. The main improvements (apart from improved engineering) were increased B-line, CRT, and magnetic drum stores, a much faster multiplier, and an increased range of instructions, for example many more B-line operations. The magnetic drum store and the multiplier were substantially redesigned.
I started working on outline processing and scripting at the University of Wisconsin in the mid 1970's. Initially, the idea came from LISP programming systems that had hierarchic program editors. I wanted to see if the same thing could be done for Pascal.
The result was a development system that ran on PDP-11s under Unix that viewed and edited source code as a tree. This embryonic outliner could dive and surface, displaying one level of the hierarchy at a time. Programmers could edit the structure of their programs directly. If you want to switch the order of two loops, just put the cursor on the latter loop statement, and move it up. No selections, no need to view the bodies of the loops. This very early piece of software met the two criteria that make something an outliner: you can control the level of detail in the display of information, and you can reorganize according to the structure of the information.
Ken Thompson used this QED at Berkeley before he came to Bell Labs, and among the first things he did on arriving was to write a new version for the MIT CTSS system. Written in IBM 7090 assembly language, it differed from the Berkeley version most notably in introducing regular expressions for specifying strings to seek within the document being edited, and to specify a substring for which a substitution should be made. Until that time, text editors could search for a literal string, and substitute for one, but not specify more general strings.
Linux is a free reimplementation of the POSIX specification, with SYSV and BSD extensions, developed primarily by Linus
Torvalds (torvalds@kruuna.helsinki.fi) at the university of Helsinki in Finland.Linux was developed with the help of other
programmers across the Internet, allowing anyone with enough knowledge to develop and change the system.
A large amount of code written for linux is developed by the GNU project at The Free Software Foundation in Cambridge,
Massachusetts.
