Hardware and Software



Alternatively referred to as a Hard Disk Drive and abbreviated as HD or HDD, the Hard Drive is the computer's main storage media device that permanently stores all data on the computer. The hard drive was first introduced on September 13, 1956 and consists of one or more hard drive platters inside of air sealed casing. Most computer hard drives are in an internal drive bay at the front of the computer and connect to the mortherboard using either ATA, SCSI, or a SATA cable and power cable. Below, is a picture of what the inside of a hard drive looks like for a desktop and laptop hard drive.


*Central Prossesing Unit (CPU)*Random Acccess Memory (RAM)*Typically, the motherboard contains the CPU, BIOS, memory, mass storage interfaces, serial and parellel ports, expanison slots, and all the controller required to control standard peripheal devices, such as the display screen, keyboared, and disk drive

The 4 Generations Of Computers

The First Generation (1945-1955) : - Programmed using machine language - No OS- Numerical calculationsThe Second Generation (1955-1965) :- Mainframes made up of transistors - Smaller computers (e.g. IBM 1401) was used to read programs and data on punch cards on to input tapes and for offline printing The Third Generation (1965-1980) :- Complex OSs as OS/360 were used. - Fixed disks were used and new jobs on cards to be executed could be read on to the disk while executing other jobs (spooling)The Fourth Generation (1980...) :- Virtual Machines and Network Computers (NCs) - Network operating systems that facilitate file sharing, remote logging etc. and Client Server computing.