revision for computing per 2016

revision for computing per 2016

1. Binary number a is a number in the binary numeral system or base-2 numeral system which represents numeric.

2. Computer software, or simply software, is that part of a computer system.

   • Disk Defragmenter is a utility in Microsoft Windows designed to increase access speed by rearranging files stored on a disk to occupy storage
   • In computer storage, fragmentation is a phenomenon in which storage space is used, reducing capacity or performance and often both.
   • anti-virus software sometimes known as anti-malware software, is computer software used to prevent, detect and remove virus.

3. We use binary logic in order to have an representation of logic gates. A digital logic circuit has a number of input lines A, B, C, ... and a number of output lines.

4. A network is defined as a group of two or more computer systems linked together.waves.A network is defined as a group of two or more computer systems linked togetherdifferent nations to connect.

   • Encryption: Encrypting data packets, when being sent over a wireless network.
   • Passwords Changed regularly to prevent access to data from malicious hackers
   • Firewall controls which programs can send or receive data packets across a network.
   • Physical Measures lock servers away, lock down equipment.
   • User access levels Different for different users. Administrators and different types of limited user.
   • Peer to peer All PCs have equal status They share resources with each other .
   • Client server Control all access to the network. Can install software across the network Share printers with computers Control the access of computers to the Internet.

5. Programming Languages is a formal computer language designed to communicate instructions to a machine, a computer. Programming languages can be used to create programs

   • A high-level language is one which is understand by us humans. It contains words and phrases from the English language. But a computer does not understand high-level language.
     • Interpreter:Translates program one statement at a time,It takes less amount of time to analyze the source code but the overall execution time is slower.
     • Compiler: Scans the entire program and translates it as a whole into machine code,It takes large amount of time to analyze the source code but the overall execution time.