Lesson 2

• A computer cannot perform any task without a computer program. Its task is to direct the computer what to do or perform.
• A computer is an electronic device that accepts digitalized data (input), process the data according to sequence of instructions (called program with mathematical and logical operations), produce some result (output), and store it for future use of the users.
• The term "computer" is derived from the Latin word "computare“, which means to calculate.
• Data is a collection of unorganized facts and figures and does not provide any further information regarding patterns, context, etc. Hence, data means "unstructured facts and figures".

  Example:

  A series of numbers: 7, 3, 9, and 15
• Information is structured data, i.e., organized, meaningful, and processed data. To process the data and convert it into information, a computer is used.

  Example:

  Using the series of numbers: 7, 3, 9, and 15 to calculate the average of the quiz score with a result of 8.5.
• Functions of Computer:

  • Input
  • Processing
  • Storage
  • Output
  • Control
  • Communication
• Input - It refers to receiving data or instructions into a computer from external resources or input devices such as a keyboard, mouse, digital pen, etc.
• Processing - It refers to the operations of the inputted data based on the list of instructions (programs) provided using the central processing unit (CPU) and other computer components to manipulate, calculate, and analyze the data.
• Storage - It refers to storing the data, information, and instructions temporarily using the primary memory (Random Access Memory (RAM)) or permanently using the secondary memory, such as hard drives, SSDs, etc.
• Output - It refers to the processed data or produced information that could be presented in the form of text, graphics, audio, or video that can be presented using a monitor, speakers, printers, etc.
• Control - It refers to controlling and managing the hardware and software components of computer systems to ensure proper operation and task execution.
• Communication - It refers to sending and receiving data or

  information over networks (such as the internet), where users can share information and other resources with others using computers.
• Identify the parts:

  A) Control Unit

  B) ALU

  C) Internal Memory

  D) Main Memory

  E) Secondary Storage

  F) Input Unit

  G) Output Unit

  
• Central Processing Unit (CPU) - is the core of a computer device and is called "the brain of the computer", where it controls theoperation of all parts of the computer system. It consists of major components: Arithmetic Logic Unit (ALU), Control Unit, and Internal Memory Unit.
• Arithmetic Logic Unit (ALU) - It refers to performing calculations and processing all the instructions, such as comparisons and decision-making.
• Control Unit - It controls all the computer activities, where it

  manages the data flow, transfers data from the memory to the ALU and vice versa and fetches the result to output devices.
• Internal Memory Unit - It refers to register memory, which is a

  volatile that stores the data, operations, or instructions that the CPU is currently processing.
• Main Memory - It refers to a primary memory called Random Access Memory (RAM).
• Storage Devices - It refers to non-volatile storage devices used for

  storing data, documents, software, etc. Such as the Hard Disk Drive (HDD), Solid State Drive (SSD), Optical Drives (CD/DVD), and USB Flash Drives.
• Motherboard - It refers to the main circuit board of the computer, which serves as the focal point of the computer system that integrates and connects every part of the system.
• Input Devices - It refers to the devices that are used to input data and instructions that allow the users to communicate with the computer.
• Output Devices - It refers to the devices that are used to display or present the processed data from the computer, which enable the user to see/hear the output.
• A computer system is a collection of complete and functional hardware and software setups with everything needed to implement computing performance. It is designed to receive, process, manage, store, and present the information in an understandable format.
• Computer Software - It refers to a programs or applications

  (intangible parts of computer) used to direct the operation of a computer, as well as documentation giving instructions on how to use them.
• Types of Software:

  ▪ System Software - It is a set of programs that controls the operations of the computer and its devices.

  ▪ Application Software - It is a set of programs that performs specific

  tasks for users.
• Computer Hardware - It refers to the physical or tangible parts of a computer, such as the input devices, output devices, storage devices, CPU, etc.
• A computer program, also known as computer software, is a sequence of instructions that is written in any programming language that instructs the computer to perform a specific task.
• The computer program is composed of two to a million lines of sequential and logical instructions (program source code) that guide the computers to execute specific operations.
• Software Developers or Programmers, who use any programming languages like Python, Java, C++, and many others.
• Key Aspects of Computer Programming

  ▪ Problem Solving

  ▪ Algorithm Design

  ▪ Data Structures

  ▪ Coding (Syntax and Logic)

  ▪ Testing and Debugging

  ▪ Documentation

  ▪ Optimization

  ▪ Modularity

  ▪ Best Practices

  ▪ Collaboration

  ▪ Version Control
• A programming language is a collection of rules and grammar used to write software applications.

  Components:

  ▪ Syntax

  ▪ Data Types

  ▪ Variables

  ▪ Operators

  ▪ Control Structures

  ▪ Libraries

  ▪ Paradigms
• Categories of Programming Languages

  • Machine Languages
  • Assembly Languages
  • High-level Languages
• Machine Languages - It refers to a language that consists of binary code that the computer can understand.
• Assembly Languages - A language that is closer to machine languages but is simpler and more readable. It use mnemonics to represent instructions.
• High-Level Languages - These are designed to be closer to human languages, human-readable, and easy to understand.
• The high-level languages used a program called compiler – a program that translates instructions written in a high-level language into equivalent program in machine language or machine code.
• Analog signals are continuously varying continuous wave forms used to represent information such as sound.
• Digital signals is a discrete signals that represent information with a sequence of 0s (low voltage/false) and 1s (high voltage/true) or binary representation or values.
• The smallest unit of digital data is a bit or binary digit, which can represent either a “0” or a “1”.
• A sequence of 8 bits forms a byte, it is the basic unit for storing and processing data in most computer systems.