තොරතුරු හා සන්නිවේදන තාක්ෂණය, නිර්මිකා දසනායක

Database Defining a Database - Collection of organized data can be defined as a database Manual database Higher the amount of data it becomes difficult to keep in our memory. On such occasions writing these data is one method. That is called manual database. Electronic database The other method is to maintain the data on an electronic medium . Advantages of   Electronic Databases ·          More efficient in retrieving  information.          ·          Easy to obtain copies. ·          Smaller physical space to store data. ·          Data analysis can be carried out efficiently. ·          Data can be shared. ·            Independence of data. Though database and software are connected, database tables can be updated without changes to the application software Features of a Database ·          Minimal data redundancy - If the same data is stored in several tables, this is called data redundancy -           By storing related database in tables

Introduction to Operating Systems A Computer consists of                                  hardware,                                  firmware                                 software.                                 Liveware Hardware Any physical component of a computer system with a definite shape is called a hardware. Examples             mouse, keyboard, display unit, hard disk, speaker, printer etc. Firmware   The booting instructions stored in the ROM (Read Only Memory) are called firmware.   The initial text information displayed on the screen are displayed by firmware. How the initial operations of a computer are performed -       When the user powers up the computer the CPU (Central Processing Unit) activates the BIOS (Basic Input Output System). -      The first program activated is POST (Power On Self-Test). Using the CMOS (Complementary Metal Oxide Semiconductor) memory   this checks all the hardware and confirms that all are f