Chapter 2 : Programming Language

-


⚠IF YOU'RE LOOKING FOR  NOTES OF CIS THEN YOU HAVE COME TO THE RIGHT PLACE ⚠




Machine Level Language

  • They are just Sequence of Numerals
  • Programs written in Binary Form
  • It is machine dependent
  • Easier for machines to understand and not illegible/ readable for humans
  • There are two parts:
  • a) opcode - command words for operations such as ADD, COMPARE, etc
  • b) operands- specifies the data, or the address of data.
  • Advantages are Fast Execution and No Translation needed.
  • Disadvantages are Error-Prone, Machine Dependent and hard to remember due to only containing 0's and 1's

Assembly Language
  • Mnemonics are used to write program in Assembly language
  • Memory locations are replaced by Hexa-decimals.
  • Assembler is used to translate Assembly Language into Machine Level Language
  • Advantages are easy to memorize, faster than high-level language and easy to understand.
  • Disadvantages are they are machine-dependent, knowledge of hardware si required and coding takes a long time.

High-Level Language
  • A high-level language is a programming language such as Java, C ++, Python, C#, C, Ruby, FORTRAN, etc.
  • They are all machine dependent language.
  • It is a high level because it is closer to human languages & far from the machine language.
  • Advantages are easy to read and write, easy to learn, programmer-friendly and easy to debug.
  • Disadvantages are it takes time to run and more memory is required for the library.

Low-Level Language
  • The programmer of low- level languages should have detailed knowledge of the computer's internal architecture and instruction set.
  • Eg: Machine language, Assembly Language


Assemblers
  • It is a program that translates Assembly Language to machine language.
  • It converts the source code ( Mnemonic code / Symbols ) into Object Code
  • Two types of assembler are One pass Assembler which performs single scan only and Two-Pass Assembler which performs two sequential scans.

     SOURCE CODE =====> ASSEMBLER ====> OBJECT CODE


Compilers
  • It is a program that translates High-Level Language to Machine Level Language.
  • Compiler takes the entire program as input, hence the errors are shown after all the program is checked.
  • Eg: Java, C, C++, etc
  • It generates an error message if found.

Interpreters
  • It takes one instruction at a time, checks it and executes one at a time.
  • If errors are found it shows it right away.
  • Eg: Python, Perl, Matlab, etc
  • Object Code is not generated


Algorithms
  • It is a step by step instruction to solve a problem.
  • Eg; Google search engine
  • In algorithms assignment of values can be done by A <== 3 which means A is equals to 3.
Properties of Algorithms:
  1. Finiteness
  2. Definiteness
  3. Input
  4. Output
  5. Effectiveness

Flow Charts
  • It is known as a diagrammatical representation of an Algorithm.
  • Advantages of Flow Chart are:
  1. Communication
  2. Effective Analysis
  3. Coding becomes easy
  4. Efficient Program Maintenance
  5. Documentation of Program/ System
  • Some Examples Questions of Flow Chart are shown below:

Three Basic Operations: Sequence, Selection, and Iteration

a) Sequence
  •  This means that the computer will run your code in order, one line at a time from the top to the bottom of your program. 
  • It will start at line 1, then execute line 2 then line 3 and so on till it reaches the last line of your program.
b) Selection ( Branching )
  • Sometimes you only want some lines of code to be run only if a condition is met, otherwise you want the computer to ignore these lines and jump over them. 
  • This is achieved using IF statements. e.g. If a condition is met then lines 4, 5, 6 are executed otherwise the computer jumps to line 7 without even looking at lines 4,5 and 6.
c) Iteration ( Repetition )
  • Sometimes you want the computer to execute the same lines of code several times. This is done using a loop. 
  • There are three types of loops: For loops, while loops and repeat until loops. 
  • That’s handy as it enables you not to have to copy the same lines of code many times.

Structured Programming
  • Structured Programming is defined as a programming paradigm that aims at improving the clarity, quality and development time of a computer program.
  • Makes use of structured control flow of selection like ( IF, ELSE, THEN ) and repetition ( WHILE or FOR ), block structures & subroutines ( functions )
  • Each module has a single entrance & exit & performs a single task.
  • Three phrases of Modular Programming are;
  • i) Top-down analysis
  • ii) Modular Programming &
  • iii) Structured Code

Features of structured programming are:
  1. Division of complex problems into small functions and procedures.
  2. No GOTO statement
  3. The main statements include - IF - THEN - ELSE, case & call statements
  4. Each module performs a specific operation.
  5. Each module has a single entry & exit point.
  6. Eg: C, C+, C++, C#, Java, PERL, Ruby, PHP.

Advantages:
  • Reuseable codes
  • Easy to represent in flowcharts and algorithms
  • Easier to read and understand
  • Easier to maintain sometimes you want the computer to execute the same lines of code several times. This is done using a loop. There are three types of loops: For loops, while loops and repeat until loops. That’s handy as it enables you not to have to copy the same lines of code many times.po
  • Require Less effort and time
  • Modularity ables many programmers to work on the same project at the same time.

Disadvantages:
  • Data is exposed to the whole program, so less data security
  • Importance given to operation rather than data.
  • Difficult to relate with real-life objects.
  • Difficult to create new data types.
  • Same code repetition. 

Object-Oriented Programming

  • OOP is defined as a programming language that is based on objects.
  • Objects collaborate by sending each other messages.
  • An object is an entity that possesses both attributes and behaviors ( methods )
  • Eg:- If a Car is an object the attributes of the car will be its color, size, weight, fuel capacity, etc and methods would be start engine, stop, turn left, etc
  • Class is the collection of objects of similar types.
  • Eg:- Grape, Bananas, Apples, Oranges are all the members of the fruits.

Features of OOP are:
  1. Object
  2. Class
  3. Abstraction
  4. Encapsulation ( Data binding )
  5. Inheritance
  6. Polymorphism
Difference between Structured Programming and OOP:

Difference between Server and Client-Side Scripting are:


Scripting Language

  • A scripting language is a programming language designed for integrating and communicating with other programming languages.
  • Widely used scripting languages are JavaScript, PHP, Perl, Python, VB Script, etc
  • Used to combine different tasks together.

Client-Side Scripting
  • Scripts that are executed on the client-side.
  • In context to website it is the scripts that execute in the browser of the user.
  • Tasks to be performed are animation, validating input and manipulating UI elements.
Server Side Scripting
  • Scripts that execute in the server
  • In the context of websites, it is a script that executes on application servers.
  • Eg: PHP, Python, etc.
  • Tasks to be performed are generating dynamic context, inserting and updating database and encoding the data into HTML.

Note: If there are any questions or incorrect things please let me know in the comments.

Comments

Post a Comment

Popular posts from this blog

Chapter 1: Introduction to Computer

-
Image
⚠IF Y OU'RE LOOKING FOR  NOTES OF CIS THEN YOU HAVE COME TO THE RIGHT PLAC E  ⚠ Definition A computer is an electronic device, operating under the control of instructions provided by the user that is stored in its own memory which accepts data (input), processes the data accordingly to specified rules, gives out information (output ) and stores data for future use. A programmable electronic device that can store. retrieve and process data. The word computer comes from the Latin word 'Compute' which means calculate. Functions of a Digital Computer  Takes data as input Store data/instructions in the memory and use them when required. Process the data and convert them into useful information. Generate output and  Control the above four operations. Block Diagram of a Computer Characteristics of a computer  1. Word Length It is defined as the unit of information that the computer can process or transfer at a ...
Read more

Chapter 4: Multimedia

-
Multimedia Multimedia is defined as the combination of contents. Example: Audio, Video, Image, Animation, and Graphics. Uses of multimedia Entertainment Music Education Marketing Virtual Reality Sales Presentation Computer-Based Training Image Quality   Image Quality is defined as a characteristic of an image that measures the perceived image degradation. Image quality is the integrated set of perception of the overall degree of excellence of an image. Factors that influence the image quality are sharpness, contrast, dynamic range, color accuracy, distortion, etc. Image File Format 1. GIF ( Graphics Interchange Format ) The most commonly used graphic file formats. Contains animation. Only capable of supporting a maximum of 256 colors. You cannot convert directly from a JPEG to GIF format. 2. JPEG ( Joint Photographic Experts Group ) It compresses files to get more graphics. Supports maximum color of 16.7 million 3. PNG ( Po...
Read more