Computer Hardware and Software Essentials
Introduction to Storage Devices
Data Storage Basics
Saving information on a computer involves assigning a binary code (0s and 1s) to each character. Early computers had limited processing power and storage capacity, using 8 bits (1 byte). Storage units increase in size: 1000B = 1KB, 1000KB = 1MB, 1000MB = 1GB, and 1000GB = 1TB. For example, 1KB is roughly equivalent to a double-spaced page of text, 1MB to a book, 1GB to a library shelf, and 1TB to a library.
Types of Computer Memory
Computer memory includes RAM and hard drives. RAM is temporary storage used when the computer is running. If RAM is full, the hard drive acts as virtual memory, but it’s much slower. The hard drive stores data persistently, even when the computer is off.
Storage Devices
- Hard Disk: Provides persistent storage with increasing capacities. Performance has improved over time, both in storage capacity and data access speed. Hard disks can be partitioned to act as multiple drives.
- CD-ROM/DVD: CD-ROMs are read-only. CD-Rs can be written to once, while CD-RWs can be written, erased, and rewritten. These use optical laser technology.
- Floppy Disk: Largely obsolete due to limited storage capacity.
- Zip Drive: Offered higher capacity than floppy disks but required a special reader.
- Pen Drive (USB Drive): Portable storage with capacities up to 32GB. Data loss can occur if damaged, so backups are recommended.
Software: A Set of Instructions
Types of Software
- Operating System Software: Manages computer operations, translating user instructions into actions.
- Applications Software: Allows users to perform specific tasks (e.g., graphics, presentations, photo editing).
- Maintenance Software: Protects the system and applications (e.g., antivirus).
Examples of operating systems include Windows XP, Windows 7, and Windows Vista.
Operating System Software
The operating system facilitates communication between the user and the computer, controlling hardware and running applications. Key functions include: controlling hardware components, running applications, and managing information storage and retrieval. MS-DOS was an early operating system that paved the way for personal computing. It was a command-line interface, unlike later window-based systems.
Applications Software
Applications software performs specific tasks. There are three main types: freeware (free to use), shareware (limited versions or time-limited trials), and paid software. Beta programs are pre-release versions used for testing. Software requirements include operating system compatibility and disk space. Portable software can run without installation. Word processors (e.g., Word, WordPerfect), spreadsheets (e.g., Excel, Lotus 123), database software (e.g., Access), and image editors (e.g., Photoshop, Paint) are common application types. Software suites offer bundled applications.
Software Development
. The software development: to improve its performance because the user can do more things.