Hardware and the Software

A computer system has two parts-hardware and the software. The hardware is useless until we do not have the requisite software. The software is necessary to run the computer. There are different types of software available.

Hardware:
Computer data processing involves equipment that can perform the following functions: data preparation; input to the computer; computation; control and primary storage; secondary storage and output from the computer. Equipment, which are
connected directly to the computer, are termed as on-line whereas the equipment, which are used separately and are not connected, are called off-line.

Software :
Software is a set of instructions that directs the computer to process information. These instructions are called programs. Without software, the computer cannot work, A commonly used analogy is that the computer hardware is the engine, while the software is the fuel that allows the engine to operate. Without relent software, the hardware would be useless. There are two types of software available for computers-system software and application software.

System Software: system software program coordinates the operations of the various hardware components of the computer. The system software or operating system program helps the user to actually operate the computer system. This is an interface between the user and the computer.

The operating system oversees the processing of the application programs all inputs to and outputs from the system. The computer manufacturers usually provide system software. The various types of computers require different types of system software program in order to operate. Some of the most popular are DOS, Windows 2000/XP and LINUX. The system software contains those programs that control and support the computer system and its data processing applications. It includes:
A. The Operating System; and
B. The Language Translators.

Operating System (OS): Considerable time is normally wasted in computer setups supervised by the operator. During compilation or assembly, run-time required to input the magnetic tape (consisting of the main program and subroutines etc ) is substantial and would naturally, be pinching. Likewise several application programs (viz, inventory control, Accounts receivables etc.) Would be read into the CPU in turn every day or so.
Operating system is an organized collection of integrated set of specialized programs that controls the overall operations of a computer. It helps the computer to supervise and manage its resources.

Language Translator :
(a) Assembler: An assembler is used to convert the program written in assembly language into machine language.
(b) Compiler: Compiler translates a source program that is usually written in aghigh level language by a programmer into machine language. The compiler is compiler is capable of replacing single source program statement with a series of machine-language instructions or with a subroutine. For each high level language the machine requires a separate compiler.
(c) Interpreter: Interpreter translates each source program statement into a sequence of machine instructions and then executes these machine instructions before translating the next source language statement. Interpreters are also unique for each high level language. Basically, the function of the compiler and interpreter are the same; the only difference is that compiler provides a separate object program but the interpreter does not.

Application Software:
Application software is a set of program designed for specific sues or applications such as word processing, graphics or spreadsheet analysis. Application software can be custom-made but is usually purchased off the shelf.
Normally to use an application program like FoxPro, we load the program into computer’s memory, execute (run) the program; and then create, edit or update a file or databas4 file. When we have finished, we need to save the work we have done on a disk. If we do not save our work and we turn off the computer, it is erased from memory and everything we have done may be lost.

Programming Languages :
A language is a system of communication. In order to communicate with each other, humans need languages like English, Hindi etc. In the same manner, for communicating with the computer, we use computer language called programming language. A programming language consists of all the symbols. Characters and usage rules that permit people to communicate with computers. Learning to program requires learning all these symbols and rules. A program is a set of l9ogically related instructions that are arranged in a sequence that guides the computer to solve a problem. The process of writing a program is called Programming.

Machine Language :
This is a sequence of instructions written in the form of binary numbers consisting of is and Os to which the computer responds directly. A machine language would have tow parts. The firs part is the command or an operation that tells the computer what functions are to be performed. The second part of the instruction is the operand that tells the computer where to find or store the data on which the desired operation is to be performed.

Assembly Language :
To ease the burden of the programmer, mnemonic operation codes and symbolic addresses were developed during the early 1950s. The Mnemonic refers to a memory aid. One of the first steps for improving the program preparation process was to substitute letter, symbols and mnemonics for the mnemonic machine-language operation codes. Today every computer has a mnemonic code, though the actual symbols vary among makes and models, Machine language is still used by the computer as it processes data but assembly language software first translates the specified operation code symbol into its machine language equivalent.
A program written by a programmer in an assembly language is called a Source program, After this source program has been converted into machine code by an assembler; it is referred to as an Object Program.

What is a Computer?

A Computer is an electronic machine with some mechanical facilities and is used mainly for data processing. It performs arithmetical and logical operations on the input data and gives the desired output. But in between the input and output, there is a step called processing which is done by the computer and processing methods on setups are provided by the users by a logical instruction known as program.



Functional Units of a computer
A computer is also a system because it is a group of integrated parts which are used to solve any problem by executing a suitable program.
Basically, there three types of functional unit of computer.
(1) Input/Output unit
(2) CPU
(3) Memory

Input/Output unit
A computer uses input devices for data entry purposes. Some input devices allow direct communication between the user and the computer. Devices connected directly to a computer are said to be on-line devices; mouse, light pen, touch screen etc. are all on-line devices.
Similar to input devices, output devices have an inter face between the user and the computer. These devices take machine coded output results from the processor and convert them into a form that can be used by human beings.

CPU(Central Processing Unit)
Central processing unit is the heart of any computer system. It consists of primary memory unit, arithmetic and logic unit and control unit.

Control Unit (CU):-Central unit controls all the hardware operations, i.e., those of output units, storage and of the processor itself. It fetches the requisite from main storage, stores it in a number of special registers, interprets the registers, interprets the instructions and follows the instructions to be executed by giving signals (or commands) to the appropriate hardware devices.

Arithmetic and Logic Unit (ALU):- The arithmetic and units in computers are capable of performing addition, subtraction, division a Subtraction, division and multiplication as well as some logical operations. The ALU has a number of selection lines to select a particular micro-operation in the unit.
Memory:-The memory or storage section of the computer consists of the devices used to store the in formation that would be used during the computations. The memory section of the computer is also used to hold both intermediate and final results as the computer proceeds through the program.
Memory can be divided into two categories-Primary Memory and Secondary Memory. Details of Primary Memory or Main Memory are as follows.
(A) RAM (Random Access Memory); and
(B) ROM (Read Only Memory).

Characteristics of a Computer
A computer is a fast and accurate electronic system that is designed to accept and store input data, process them and produce output results using the instructions of a stored program.
Speed and Accuracy :-Computer executes one instruction at a time. It can add and subtract numbers, compare characters to determine string matching and copy numbers and characters. There is nothing new in these operations.
In additions to their high speeds, computers have high accuracies as well. The circuits in a computer have electronic parts which do not have wear and tear.
Processing Capabilities:- Computer processing involves manipulating the symbols that represent things required by the user. People have been using characters, numbers and other symbols and computer processing simplifies this human task by providing the necessary speed and accuracy.
Data and Information:-Data are represented by symbols. After processing the data, information is produced. Thus information is data arranged in an order that would be useful to the user.
Data processing consists of three basic activities.
(1) Capturing the input data
(2) Manipulating the data and
(3) Handling the output results.

Capturing the input data: Data must be recorded or captured on some medium before they could be processed.
Manipulating the data: The following operations may be performed on the data.

(A) Classifying:
(B) Calculating:
(C) Storing:
(D) Summarising:

Handling the output results: Once data have been captured and manipulated, one or more of the following operations may be needed.

(A)Storing and Retrieving:
(B)Communicating and Reproducing:

Computer Processing Operations: A computer can perform only the following four basic operations through it can carry out the data processing activities.
(1) Input\Output operations
(2) Text manipulation and calculation operations
(3) Logic\Comparison operations
(4) Storage and Retrieval operations

Memory Capability

Computer systems have the ability of total and instant recall of data and an almost unlimited capacity to store these data. A typical mainframe computer system would have billions of characters and perhaps, thousands of graphic images, stored and available for instant recall.

100 keyboard shortcuts

Hi,
Today i have posted these 100 keyboard shortcuts.
Pls Check it out.

CTRL+X (Cut)
CTRL+V (Paste)
CTRL+Z (Undo)
DELETE (Delete)
SHIFT+DELETE (Delete the selected item permanently without placing the item in the Recycle Bin)
CTRL while dragging an item (Copy the selected item)
CTRL+SHIFT while dragging an item (Create a shortcut to the selected item
F2 key (Rename the selected item)
CTRL+RIGHT ARROW (Move the insertion point to the beginning of
the next word)
CTRL+LEFT ARROW (Move the insertion point to the beginning of the
previous word)
CTRL+DOWN ARROW (Move the insertion point to the beginning of the
next paragraph)
CTRL+UP ARROW (Move the insertion point to the beginning of the
previous paragraph)
CTRL+SHIFT with any of the arrow keys (Highlight a block of text)
SHIFT with any of the arrow keys (Select more than one item in a
window or on the desktop, or select text in a document)
CTRL+A (Select all)
F3 key (Search for a file or a folder)
ALT+ENTER (View the properties for the selected item)
ALT+F4 (Close the active item, or quit the active program)
ALT+ENTER (Display the properties of the selected object)
ALT+SPACEBAR (Open the shortcut menu for the active window)
CTRL+F4 (Close the active document in programs that enable you to have multiple documents open simultaneously)
ALT+TAB (Switch between the open items)
ALT+ESC (Cycle through items in the order that they had been
opened)
F6 key (Cycle through the screen elements in a window or on the
desktop)
F4 key (Display the Address bar list in My Computer or Windows
Explorer)
SHIFT+F10 (Display the shortcut menu for the selected item)
ALT+SPACEBAR (Display the System menu for the active window)
CTRL+ESC (Display the Start menu)
ALT+Underlined letter in a menu name (Display the corresponding
menu)
Underlined letter in a command name on an open menu (Perform the
corresponding command)
F10 key (Activate the menu bar in the active program)
RIGHT ARROW (Open the next menu to the right, or open a submenu)
LEFT ARROW (Open the next menu to the left, or close a submenu)
F5 key (Update the active window)
BACKSPACE (View the folder one level up in My Computer or Windows
Explorer)
ESC (Cancel the current task)
SHIFT when you insert a CD-ROM into the CD-ROM drive (Prevent the
CD-ROM from automatically playing)

Dialog Box Keyboard Shortcuts
CTRL+TAB (Move forward through the tabs)
CTRL+SHIFT+TAB (Move backward through the tabs)
TAB (Move forward through the options)
SHIFT+TAB (Move backward through the options)
ALT+Underlined letter (Perform the corresponding command or
select the corresponding option)
ENTER (Perform the command for the active option or button)
SPACEBAR (Select or clear the check box if the active option is a
check box)
Arrow keys (Select a button if the active option is a group of option
buttons)
F1 key (Display Help)
F4 key (Display the items in the active list)
BACKSPACE (Open a folder one level up if a folder is selected in
the Save As or Open dialog box)
MicroSoft Natural Keyboard Shortcuts Windows Logo (Display or hide the Start menu)
Windows Logo+BREAK (Display the System Properties dialog box)
Windows Logo+D (Display the desktop)
Windows Logo+M (Minimize all of the windows)
Windows Logo+SHIFT+M (Restore the minimized windows)
Windows Logo+E (Open My Computer)
Windows Logo+F (Search for a file or a folder)
CTRL+Windows Logo+F (Search for computers)
Windows Logo+F1 (Display Windows Help)
Windows Logo+ L (Lock the keyboard)
Windows Logo+R (Open the Run dialog box)
Windows Logo+U (Open Utility Manager)

Accessibility Keyboard Shortcuts
Right SHIFT for eight seconds (Switch FilterKeys either on or
off)
Left ALT+left SHIFT+PRINT SCREEN (Switch High Contrast either on
or off)
Left ALT+left SHIFT+NUM LOCK (Switch the MouseKeys either on or
off)
SHIFT five times (Switch the StickyKeys either on or off)
NUM LOCK for five seconds (Switch the ToggleKeys either on or
off)
Windows Logo +U (Open Utility Manager)
Windows Explorer Keyboard Shortcuts
END (Display the bottom of the active window)
HOME (Display the top of the active window)
NUM LOCK+Asterisk sign (*) (Display all of the subfolders that
are under the selected folder)
NUM LOCK+Plus sign (+) (Display the contents of the selected
folder)
NUM LOCK+Minus sign (-) (Collapse the selected folder)
LEFT ARROW (Collapse the current selection if it is expanded, or
select the parent folder)
RIGHT ARROW (Display the current selection if it is collapsed, or
select the first subfolder) After you double-click a character on the grid of characters, you can move through the grid by using the keyboard shortcuts:
RIGHT ARROW (Move to the right or to the beginning of the next
line)
LEFT ARROW (Move to the left or to the end of the previous line)
UP ARROW (Move up one row)
DOWN ARROW (Move down one row)
PAGE UP (Move up one screen at a time)
PAGE DOWN (Move down one screen at a time)
HOME (Move to the beginning of the line)
END (Move to the end of the line)
CTRL+HOME (Move to the first character)
CTRL+END (Move to the last character)
SPACEBAR (Switch between Enlarged and Normal mode when a
character is selected)

MicroSoft Management Console (MMC) Main Window Keyboard Shortcuts
CTRL+O (Open a saved console)
CTRL+N (Open a new console)
CTRL+S (Save the open console)
CTRL+M (Add or remove a console item)
CTRL+W (Open a new window)
F5 key (Update the content of all console windows)
ALT+SPACEBAR (Display the MMC window menu)
ALT+F4 (Close the console)
ALT+A (Display the Action menu)
ALT+V (Display the View menu)
ALT+F (Display the File menu)
ALT+O (Display the Favorites menu)

MMC Console Window Keyboard Shortcuts
CTRL+P (Print the current page or active pane)
ALT+Minus sign (-) (Display the window menu for the active
console window)
SHIFT+F10 (Display the Action shortcut menu for the selected
item)
F1 key (Open the Help topic, if any, for the selected item)
F5 key (Update the content of all console windows)
CTRL+F10 (Maximize the active console window)
CTRL+F5 (Restore the active console window)
ALT+ENTER (Display the Properties dialog box, if any, for the
selected item)
F2 key (Rename the selected item)
CTRL+F4 (Close the active console window. When a console has only
one console window, this shortcut closes the console)

Remote Desktop Connection Navigation
CTRL+ALT+END (Open the MicroSoft Windows NT Security dialog box)
ALT+PAGE UP (Switch between programs from left to right)
ALT+PAGE DOWN (Switch between programs from right to left)
ALT+INSERT (Cycle through the programs in most recently used
order)
ALT+HOME (Display the Start menu)
CTRL+ALT+BREAK (Switch the client computer between a window and a
full screen)
ALT+DELETE (Display the Windows menu)
CTRL+ALT+Minus sign (-) (Place a snapshot of the active window in
the client on the Terminal server clipboard and provide the same
functionality as pressing PRINT SCREEN on a local computer.)
CTRL+ALT+Plus sign (+) (Place a snapshot of the entire client
window area on the Terminal server clipboard and provide the same
functionality as pressing ALT+PRINT SCREEN on a local computer.)

MicroSoft Internet Explorer Navigation
CTRL+B (Open the Organize Favorites dialog box)
CTRL+E (Open the Search bar)
CTRL+F (Start the Find utility)
CTRL+H (Open the History bar)
CTRL+I (Open the Favorites bar)
CTRL+L (Open the Open dialog box)
CTRL+N (Start another instance of the browser with the same Web
address)
CTRL+O (Open the Open dialog box, the same as CTRL+L)
CTRL+P (Open the Print dialog box)
CTRL+R (Update the current Web page)
CTRL+W (Close the current window )
CTRL+C (Copy)
CTRL+X (Cut)
CTRL+V (Paste)
CTRL+Z (Undo)
DELETE (Delete)
SHIFT+DELETE (Delete the selected item permanently without
placing the item in the Recycle Bin)
CTRL while dragging an item (Copy the selected item)
CTRL+SHIFT while dragging an item (Create a shortcut to the
selected item)
F2 key (Rename the selected item)
CTRL+RIGHT ARROW (Move the insertion point to the beginning of
the next word)
CTRL+LEFT ARROW (Move the insertion point to the beginning of the
previous word)
CTRL+DOWN ARROW (Move the insertion point to the beginning of the
next paragraph)
CTRL+UP ARROW (Move the insertion point to the beginning of the
previous paragraph)
CTRL+SHIFT with any of the arrow keys (Highlight a block of text)
SHIFT with any of the arrow keys (Select more than one
item in a window or on the desktop, or select text in a document)
CTRL+A (Select all)
F3 key (Search for a file or a folder)
ALT+ENTER (View the properties for the selected item)
ALT+F4 (Close the active item, or quit the active program)
ALT+ENTER (Display the properties of the selected object)
ALT+SPACEBAR (Open the shortcut menu for the active window)
CTRL+F4 (Close the active document in programs that enable you to
have multiple documents open simultaneously)
ALT+TAB (Switch between the open items)
ALT+ESC (Cycle through items in the order that they had been
opened)
F6 key (Cycle through the screen elements in a window or on the
desktop)
F4 key (Display the Address bar list in My Computer or Windows
Explorer)
SHIFT+F10 (Display the shortcut menu for the selected item)
ALT+SPACEBAR (Display the System menu for the active window)
CTRL+ESC (Display the Start menu)
ALT+Underlined letter in a menu name (Display the corresponding
menu)Underlined letter in a command name on an open menu (Perform the
corresponding command)
F10 key (Activate the menu bar in the active program)
RIGHT ARROW (Open the next menu to the right, or open a submenu)
LEFT ARROW (Open the next menu to the left, or close a submenu)
F5 key (Update the active window)
BACKSPACE (View the folder one level up in My Computer or Windows
Explorer)
ESC(Cancel the current task)
SHIFT when you insert a CD-ROM into the CD-ROM drive
(Prevent the CD-ROM from automatically playing)

With warm regards,
Abhishek (Abhi)
For Tech Support

Introduction

Hi,
I am Abhishek Verma from India.
I am working in as a Java Programmer in New Delhi, India.
I have created this blog to post programming code and to get the same.
I feel very happy if you post comments.....

With Regards,
Abhishek Verma
abhishek.verma4u@yahoo.com