Introduction to object oriented programming concepts

• Computer


  An electronic device that accepts instructions in a specific language
• It is very difficult to establish communication between the user and the computer if he/she is not aware of computer language
• Types of computer languages

  • High Level Language
  • Low Level Language
• Low Level Languages


  Computer recognizes the instructions, without conversion into any other form
• Types of Low Level Languages

  • Machine Language
  • Assembly Language
• Machine Language


  Instructions are coded in terms of binary digits (bits), i.e. in the form of zeroes and ones (0's and 1's)
• Assembly Language


  Instructions are coded in terms of mnemonics (or operation codes)
• Assembly Language


  • Easier to write instructions compared to machine language
  • Error detection and correction is comparatively easier
  • Code can easily be modified
• Assembly language is also a machine dependent language
• Users need to remember all the mnemonics in assembly language
• A translator is required to convert assembly language instructions into machine code
• High Level Languages (HLLs)


  Instructions can be written using logical words or phrases, easier to understand and develop program logic
• High Level Languages


  • Machine independent
  • Error detection and correction is easier
• High level language requires a translator to convert the source code (program) into machine code</b>
• Machine code of high level instructions might be less efficient than the machine code generated from assembly language instructions
• Compiler


  Software that accepts the whole program written in high level language and converts it into its equivalent program in machine language
• Interpreter


  Software that accepts the program line by line, converts it into machine language, and executes it immediately
• Compiler is comparatively faster than the interpreter but sometimes more difficult to use as it displays all the errors together
• Types of High Level Languages

  • Procedure Oriented Programming Languages
  • Object Oriented Programming Languages
• Procedure Oriented Programming (POP)


  Instructions for the computer to follow are organized into groups known as functions
• Procedure Oriented Programming (POP)


  • Emphasis on logical steps
  • Data flows from one function to another
• Limitations of Procedure Oriented Programming (POP) include complex programs, global data access
• Object Oriented Programming (OOP)

  Approach to designing programs by creating self-contained units called objects, each containing both data and related functions
• Object Oriented Programming (OOP)


  • Data is protected and separate from external functions
  • Allows for code reuse and modularity
• Procedure Oriented Programming (POP)


  Rather than the data, the focus is on the procedures
• Procedure Oriented Programming (POP)

  • Monolithic structure
  • Top-down approach
• Object Oriented Programming (OOP)


  Approach to designing software by creating partitions called objects
• Object Oriented Programming (OOP)

  • Data and functions are organised together in objects
  • Data can only be accessed through the associated functions
  • Allows data hiding
• Object Oriented Programming (OOP) is a powerful tool in programming due to the feature of data hiding
• Some of the key benefits of Object Oriented Programming (OOP) include code reusability, modularity, and data abstraction
• Differences between Procedural Oriented Programming (POP) and Object Oriented Programming (OOP)

  • Focus on procedures vs focus on data
  • Monolithic structure vs modular structure
  • Top-down approach vs bottom-up approach
• Object


  Unique entity containing data and functions (characteristics and behaviour)
• Real World Object


  Objects we experience or use in day-to-day life, containing characteristics and behaviour
• Basic Principles of Object Oriented Programming (OOP)

  • Encapsulation
  • Inheritance
  • Polymorphism
  • Data Abstraction
• Data Abstraction


  Presenting the essential features without revealing the background details
• Inheritance


  Acquiring properties of one class by another class
• Polymorphism


  Ability of an operation to exhibit different behaviours for different sets of data and environment
• Encapsulation


  Restricting the free flow of data from one object to another by wrapping data and functions together
• Benefits of Object Oriented Programming (OOP) include improved code reusability, modularity, and data abstraction
• Limitations of Object Oriented Programming (OOP) include more time-consuming problem solving and the need for a thorough understanding of the concepts