Data recoveryYou may be happily using a computer, and storing all the data and information on your computer and one day boooom, your computer stops working. You have not backed up your data. What you do now?
You may resort to data recovery, which is a process of recovering data from primary storage media when it cannot be accessed normally. The recovery is possible when you lose date due to physical damage to the storage device or logical damage to the file system that prevents it from being mounted by the host operating system. For simplicity we can divide data recovery into these two sections.........Go to data recovery
Computer BasicsA computer is a machine capable of processing data according to a program - a list of instructions. The data to be processed may represent many types of information including numbers, text, pictures, or sound. Computers can be extremely versatile. In fact, they are universal information processing machines. According to the Church-Turing thesis, a computer with a certain minimum threshold capability is in principle capable of performing the tasks of any other computer, from those of a personal digital assistant to a supercomputer. Therefore, the same computer designs have been adapted for tasks from processing company payrolls to controlling industrial robots.........Go to computer basics
Computer ApplicationsThe first electronic digital computers, with their large size and cost, mainly performed scientific calculations, often to support military objectives. The ENIAC was originally designed to calculate ballistics-firing tables for artillery, but it was also used to calculate neutron cross-sectional densities to help in the design of the hydrogen bomb. This calculation, performed in December, 1945 through January, 1946 and involving over a million punch cards of data, showed the design then under consideration would fail. (Many of the most powerful supercomputers available today are also used for nuclear weapons simulations.) The CSIR Mk I, the first Australian stored-program computer, evaluated rainfall patterns for the catchment area of the Snowy Mountains Scheme, a large hydroelectric generation project.........Go to computer applications
computer ProgramsComputer programs are simply lists of instructions for the computer to execute. These can range from just a few instructions which perform a simple task, to a much more complex instruction list which may also include tables of data. Many computer programs contain millions of instructions, and many of those instructions are executed repeatedly. A typical modern PC (in the year 2005) can execute around 3 billion instructions per second. Computers do not gain their extraordinary capabilities through the ability to execute complex instructions. Rather, they do millions of simple instructions arranged by people known as programmers. In practice, people do not normally write the instructions for computers directly in machine language. Such programming is incredibly tedious and highly error-prone, making programmers very unproductive.
.........Go to computer Programs
|
|
Digital CircuitsThe conceptual design above could be implemented using a variety of different technologies. As previously mentioned, a stored program computer could be designed entirely of mechanical components like Babbage's. However, digital circuits allow Boolean logic and arithmetic using binary numerals to be implemented using relays - essentially, electrically controlled switches. Shannon's famous thesis showed how relays could be arranged to form units called logic gates, implementing simple Boolean operations. Others soon figured out that vacuum tubes - electronic devices, could be used instead. Vacuum tubes were originally used as a signal amplifier for radio and other applications, but were used in digital electronics as a very fast switch; when electricity is provided to one of the pins, current can flow through between the other two..........Go to digital circuits
History of ComputingThe first general purpose programmable electronic computer was the Electronic Numerical Integrator and Computer (ENIAC), built by J. Presper Eckert and John V. Mauchly at the University of Pennsylvania. Work began in 1943, funded by the Army Ordnance Department, which needed a way to compute ballistics during World War II. The machine wasn't completed until 1945, but then it was used extensively for calculations during the design of the hydrogen bomb. By the time it was decommissioned in 1955 it had been used for research on the design of wind tunnels, random number generators, and weather prediction. Eckert, Mauchly, and John von Neumann, a consultant to the ENIAC project, began work on a new machine before ENIAC was finished. The main contribution of EDVAC, their new project, was the notion of a stored program. ..........Go to history of computing
computer CablesThe standard type of cable used to connect networks together is called a straight through cable. It's also referred to by several other names, such as CAT 5 cable, network cable or patch cable, but they all refer to the same type of cable.10BaseT does not have a distinct maximum cable length ? 100 to 150 metres is the generally accepted limit, but high grade low loss cable can extend this. This maximum length is the distance each computer can be from its hub, not the total cable length in the system, so a single $200 17-port hub makes it easy to cable up a good-sized office.
.........Go to computer cables
|
|
|
Net World Directory
