Computer Essentials (Lesson 1) PDF

Computer Essentials \[Lesson 1\] ================================ Computer : A computer is an electronic device that can receive, store, process, and output data based on a set of instructions (programs). It is designed to execute applications and provides a variety of solutions by combining integr...

Computer Essentials \[Lesson 1\] ================================ Computer : A computer is an electronic device that can receive, store, process, and output data based on a set of instructions (programs). It is designed to execute applications and provides a variety of solutions by combining integrated hardware and software components. ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- **Information processing cycle** - The core operations of a computer, often referred to as the computer\'s \"information processing cycle,\" can be broken down into four basic actions: 1. **Input**: This is the process by which data and instructions are given to the computer. Devices such as keyboards, mice, scanners, cameras, and microphones are commonly used *for input*. 2. **Processing**: Once the data is inputted, the computer\'s central processing unit (CPU) processes the information. This means it performs operations on the data, like arithmetic or logic operations, based on the instructions provided. 3. **4. Output:** Once data has been inputted and processed, the computer displays or outputs the results. This can be in the form of visual display on a monitor, printed on paper, played through speakers, saved to a file, or transmitted to another computer or device. Output devices include monitors, printers, and speakers. - **Storage**: After or during processing, the computer saves data in its memory. There are various levels of storage, including: - **Primary** **storage**: Temporary storage (like RAM) *that provides fast access for the CPU to data and instructions while the computer is running.* - **Secondary** **storage**: Long-term storage (like hard drives, SSDs, or external storage devices) *where data, applications, and the operating system reside.* **Data vs Information** - Both \"data\" and \"information\" are fundamental concepts in the realm of computing and information systems, but they have distinct meanings: - refers to raw facts and figures without any context. It can be any character, text, word, number, or even a bit or a byte. Example: a sequence of numbers like \"19930315\" or a list of names without context. - **Transistors in computers are used as electronic switches to represent binary values. At a basic level, a transistor in a digital circuit can be in one of two states, which correspond to the binary values of 0 and 1.** - **Off State: When a transistor is \"off\" or in a non-conductive state, it does not allow current to pass through. *[This state represents the binary value 0. ]*** - **On State: When a transistor is \"on\" or in a conductive state, it allows current to flow through. [*This state represents the binary value 1*.]** **Measurement Units** - **In computing, data storage and processing are quantified using a hierarchy of units. The foundational unit is the \"bit,\" and from there, we scale up. Here\'s a breakdown of these units, starting from the smallest:** **- Conversion (in binary): 1 MB = 1,024 KB** - **Gigabyte:** - **- Symbol: GB** - **- Definition: Gigabyte is a higher order of magnitude and is commonly used today to represent storage capacities, especially for hard drives, SSDs, and USB sticks.** - **- Conversion (in binary): 1 GB = 1,024 MB** **Example:** - **The hexadecimal (base-16) system is widely used in computing because of its concise representation of binary data and its ease of conversion to and from binary. In the hexadecimal system, numbers can be represented using the digits 0-9 and the letters A-F (or a-f), with \'A\' representing 10, \'B\' representing 11, and so on up to \'F\' representing 15.** - **Color Representation in Web Design:** - **Red:** - **- RGB(255, 0, 0)** - **- Hex: \`\#FF0000\`** - **Green:** - **- RGB(0, 255, 0)** - **- Hex: \`\#00FF00\`** - **Blue:** - **- RGB(0, 0, 255)** - **- Hex: \`\#0000FF\`** - **How computers use these encoding tables?** - **ASCII (American Standard Code for Information Interchange)** - **Unicode** - **Usage in Computers: UTF-16: This encoding uses either one or two 16-bit code units per character, making it suitable for representing a wider range of characters directly. Unicode can represent special characters, emojis, and many international symbols *[that ASCII cannot.]*** **Computer types** - **Computers can be categorized based on their size, capability, and purpose. Here\'s a list of various types of computers:** - **Supercomputers:** - **Purpose: Used for complex, high-end computations.** - **Examples: Weather forecasting, molecular research, simulations.** - **Mainframe Computers:** **Purpose[: Handle large amounts of data, support multiple users simultaneously, and run commercial applications.]** **Examples: Transaction processing for large organizations like banks, airline reservations.** - **Servers:** **Purpose: Serve data to other computers (clients) on a network.** **Examples: Schools and universities use servers to provide students and staff with access to resources such as online courses, research databases, and email.** - **Microcomputers (Personal Computers):** - **Desktop Computers: General-purpose computers for individual users.** - **Laptop Computers: Portable version of desktops.** - **Netbooks: Smaller laptops primarily for internet use.** - **Tablets: Touchscreen-based, like Apple\'s iPad or Samsung\'s Galaxy Tab.** - **Workstations:** **Purpose: More powerful than personal computers, used for tasks needing better graphics or computational power.** **Examples: Video editing, CAD design, 3D design tasks.**