Computer Programming

• A Computer is an electronic device that accepts data from user, process it, produces results, displays them to users, and stores result for future usage.
• A Data is a collection of unorganized or unstructured facts and figures. Does not only provide information regarding patterns, contexts, etc.
• Information is a structured data (organized meaningful and processed data)
• A computer is used to process data and convert it into information.
• A hardware is a mechanical device that makes up computer. It also consists of interconnected electronic devices that we can use to control computer's operation, input, and output.
• A program is a set of instructions that drives computer to do stipulated tasks.
• A software is an instructions that are programmed in a computer language translated into machine language, and executed by computer.
• There are two types of software:

  1. System software- operates directly on hardware devices of computer. It provides platform to run an application.
  2. Application software- designed for benefit of users to perform one or more tasks.
• Computer programming is the process of designing and implementing algorithms using programming languages
• Programming Languages - A human readable language which allows us to communicate with computers.
• What are the two types of software?

  System and application software
• A programming is an act of writing instructions that consists of statements in a form of specific programming language.
• 5 step process of programming:

  1. Define the problem
  2. Design the solution or program
  3. code the program
  4. test the program
  5. document the program
• IPO = input,process,output
• Input- The data entered into the computer system by user or other devices.
• Process- It refers to the set of operations performed on the given inputs to produce desired outputs.
• Output- The result produced as a consequence of processing the input data.
• Data, Answerable by  Data types: Integer, Float, Character
• GIGO = GARBAGE INPUT, GARBAGE OUTPUT
• PIPO = PERFECT INPUT, PERFECT OUTPUT
• ROGRAM DEVELOPMENT PROCEDURE (PROGRAM LIFE CYCLE)

  • Program/Problem Definition
  •  Program Design
  •  Program Coding 
  •  Program Testing 
  • Program Documentation 
  • Program Maintenance
• Debugging means detecting, locating and removing errors in the computer program.
• An algorithm is a step by step procedure to solve a given problem.
• three types of errors:

  1. syntax errors
  2. logic errors
  3. system error
• syntax errors is a type of error that can be typographical error or incorrect format of the statement used.
• logic errors is a type of error caused by incorrect use of control structures.
• System errors is a type of predefined error codes and error messages that software programmers can use with their software to tell you (the software user) that the program is experiencing a particular problem
• An algorithm must have five properties: input specified, output specified, output precision specified, definiteness, and effectiveness.
• Input specified in an algorithm means that the data, its quantity, and its form are known.
• Output specified in an algorithm is the data resulting from the computation, which is the intended result.
• Output precision in an algorithm requires specifying the kind of data, its quantity, and its form.
• Definiteness in an algorithm means specifying the sequence of operations for turning input into output.
• Effectiveness in an algorithm means that all of its steps are doable.
• Finiteness in an algorithm means that stopping may result in the expected output or in a response that no solution is possible.
• A flowchart is a visual representation of the sequence of the steps and decisions needed to perform a process.
• A flowchart is a type of diagram that represents an algorithm or process.
• In flowchart, what symbol is this?

  input and output symbol

  
• In flowchart, what symbol is this?

  process symbol

  
• In flowchart, what symbols is this?

  decision symbol

  
• Flowchart, what symbol is this?

  arrow/flow lines