Professional English-2: TEXTS TO BE TRANSLATED & Homework-6

.... (a paragraph from) Evolution of Operating Systems

In 1960s, several groups in industry and the universities pioneered timesharing operating systems. Timesharing is a special case of multiprogramming in which users access the computer through terminals, typically devices with keyboards and screens. In a typical timesharing computer system, there may be dozens or even of hundreds users sharing the computer at once. The computer does not actually run all the users simultaneously. Rather, it runs a small portion of one user’s job then moves on to service the next user. The computer does this so quickly that it may provide service to each user several times per second. Thus the users’ programs appear to be running simultaneously.

History of C and C++

C++ evolved from C, which evolved from previous two programmimg languages, BPCL and B. (.....). The C language was evolve from B by Dennis Ritchie at Bell Laboratories and was originally implemented on a DEC PDP-11 computer in 1972. C uses many important concepts pf BPCL and B while adding data typing and many other features. C initially became widely known as the development language of the UNIX operating system. Today, most operating systems are written in C and/or C++. C is now available for most computers. C is hardware independent. With careful design, it is possible to write C programs that are portable to most computers.


Writing the C++ Statements

Write a C++ statement to accomplish each of the following tasks:

a) Declare a variable sum and x to be of type int.
b) Initialize variable x to 1.
c) Initialize variable sum to 0.
d) Add variable x to variable sum and assign the result to variable sum.
e) Print "The sum is: " followed by the value of variable sum.


Homework-6: Personal Computing, Distributed Computing and Client/Server Computing

In 1977, Apple Computer popularized the phenomenon of personal computing. Initially, it was a hobbyist’s dream. Computers became economical enough for people to buy them for their own personal or business use. In 1981, IBM, the world’s largest computers vendor, introduced the IBM Personal Computer. Literally overnight, personal computing became legitimate in business, industry and government organizations (........ ).

Although early personal computers were not powerful enough to timeshare several users, these machines could be linked together in computer networks, sometimes over telephone lines and sometimes in LANs within an organization. This led to the phenomenon of distributed computing in which an organization’s computing, instead of being performed strictly at some central computer installation, is distributed over networks to the sites at which the work of organization is performed. (............)

Today’s most powerful personal computers are as powerful as the million dollar machines of just a decade ago. The most powerful desktop machines - called workstations - provide individual users with enormous capabilities. Information is easily shared across computer networks where some computers are called file servers offer a common store of programs and data that may be used by client computers distributed throughout the network.