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Unit 2: RedHat Linux Basics

Software which provides a desktop environment might also provide drag and drop functionality notes
and other features which make the desktop metaphor more complete. On the whole, a desktop
environment is to be an intuitive way for the user to interact with the computer using concepts
which are similar to those used when interacting with the physical world, such as buttons and
windows.
While the term desktop environment originally described a style of user interfaces following
the desktop metaphor, it has also come to describe the programs that provide the metaphor
itself. This usage has been popularized by the Gnome and the K Desktop Environment. Today,
GNOME and KDE are the dominant solutions, and often installed by default on Linux systems.
2.1 working with Desktop

In the past, huge mainframe computers with character-cell terminals used to be the only cost
effective solution for institutions requiring operating systems that supported multiple users,
number crunching power, and large databases. Personal computers and workstations were either
too expensive or lacked the capabilities provided by mainframes. This resulted in the proliferation
of mainframes in work settings that needed to share data and resources: colleges, universities,
design engineering and research companies, hospitals, banking, and accounting firms.
Due to better technology and decreased costs, however, desktop workstations began to perform
the same functions as a mainframe at a fraction of the cost. This provided an attractive alternative
for institutions wishing to replace or upgrade their out-of-date mainframes, and created a large
workstation market supplied by several companies that designed and developed their own
workstation products.

Did u know? What is the role of vendors in supplying a graphical user interface?

predecessors

Several bitmap display systems preceded X. From Xerox came the Alto (1973) and the Star (1981).
From Apple came the Lisa (1983) and the Macintosh (1984). The Unix world had the Andrew
Project (1982) and Rob Pike’s Blit terminal (1982).
Carnegie-Mellon University produced a remote-access application called Alto Terminal, that
displayed overlapping windows on the Xerox Alto, and made remote hosts (typically DEC
VAX systems running Unix) responsible for handling window-exposure events and refreshing
window contents as necessary.
X derives its name as a successor to a pre-1983 window system called W (the letter preceding X in
the English alphabet). W Window System ran under the V operating system. W used a network
protocol supporting terminal and graphics windows, the server maintaining display lists.

origin and early Development

The original idea of X emerged at MIT in 1984 as a collaboration between Jim Gettys (of Project
Athena) and Bob Scheifler (of the MIT Laboratory for Computer Science). Scheifler needed a
usable display environment for debugging the Argus system. Project Athena (a joint project
between Digital Equipment Corporation (DEC), MIT and IBM to provide easy access to computing
resources for all students) needed a platform-independent graphics system to link together
its heterogeneous multiple-vendor systems; the window system then under development in
Carnegie Mellon University’s Andrew Project did not make licenses available, and no alternatives
existed.

LoveLy professionaL university 29