JavaScript – Learning notes – part 1


  • Data types
  • Numbers, strings, boolean, objects, functions, undefined values

  1.  Numbers: numeric values. Fixed number of bits of 64 for representation(2^64 different numbers). 3 Special numbers are infinity, -infinity, NaN( Not a Number)
  2. Strings: represented with single or double quotes. \ is used for escaping character.
  3. Boolean: true or false
  4. Undefined values: null and undefined.


    1. Arithmetic operators: +,-,/,*,%
    2. Unary operators: typeof, !
    3. Logical operators: &&, ||
    4.  Conditional operators: ?:(ternary operator)

    Type Conversion:

    * When an operator is applied to the wrong type of value, JS will convert that value to the type it wants( Type Coercion ) 

    Eg: 8*null -> 0

            “5” – 1  -> 4


    java 8 installation

    $ sudo add-apt-repository ppa:webupd8team/java
    $ sudo apt-get update
    $ sudo apt-get install oracle-java8-installer
    java -version
    java version "1.8.0_91"
    Java(TM) SE Runtime Environment (build 1.8.0_91-b14)
    Java HotSpot(TM) 64-Bit Server VM (build 25.91-b14, mixed mode)
    sudo apt-get install oracle-java8-set-default

    Web development testing tools and sites

    I came across this recently while studying the web development courses.

    This helps in faster testing of your code by synchronizing file changes and creates a temporary server.


    npm install -g browser-sync

    Start Browser sync
    In your project folder
    browser-sync start --server --directory --files "*"
    Below sites will also be helpful for testing:
    Site to check Standards and compatibility:
    Important links:
    To test the network issues or delays:
    ctrl + shift + i - chrome development tools
    network tab -  A throttling setting , Change setting 
    Web designing mockup: (not free)