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Day 1 Excersice 1 & 2

Day-1

Day 1 Excersice 1 & 2 Excersice 1.docx

1. Write a blog on Difference between HTTP1.1 vs HTTP2

Sno HTTP HTTPS 1 HTTP stands for HyperText Transfer Protocol. HTTPS for HyperText Transfer Protocol Secure. 2 In HTTP, URL begins with “http://”. In HTTPs, URL starts with “https://”. 3 HTTP uses port number 80 for communication. HTTPs uses 443 port number for communication. 4 HTTP is considered to be unsecure. HTTPs is considered as secure. 5 HTTP works at Application Layer. HTTPS works at Transport Layer. 6 In HTTP, Encryption is absent. Encryption is present in HTTPS.

7 HTTP does not require any certificates. HTTPS needs SSL Certificates. 8 HTTP does not improve search ranking HTTPS helps to improve search ranking 9 HTTP faster than HTTPS HTTPS slower than HTTP 10 HTTP does not use data hashtags to secure data. While HTTPS will have the data before sending it and return it to its original state on the receiver side. 11 HTTP does not scramble the data to be transmitted. That’s why there is a higher chance that transmitted information is available to hackers. HTTPS scrambles the data before transmission. At the receiver end, it descrambles to recover the original data. Therefore, the transmitted information is secure which can’t be hacked. 12 It operates at TCP/IP level. HTTPS does not have any separate protocol. It operates using HTTP but uses encrypted TLS/SSL connection. 13 HTTP does not improve search rankings. HTTPS helps to improve search ranking. 14 Fast Slower than HTTP 15 Vulnerable to hackers It Is highly secure as the data is encrypted before it is seen across a network.

Excersice 2.docx

2. Write a blog about objects and its internal representation in Javascript

Objects: All individual objects possess three basic characteristics -- identity, state and behavior. Understanding these characteristics is crucial to knowing how objects and object-oriented logic work.

• Identity means that each object has its own object identifier and can be differentiated from all other objects. Each object's name, or identity, is unique and distinct from other objects. • State refers to the properties of an object. For example, values of variables in the object contain data that can be added, changed or deleted. • Behavior refers to actions that the object can take. For example, one object can respond to another object to carry out software functions. Some of the things in programming that can be defined as objects include the following: • variables, which hold values that can be changed; • data structures, which are specialized formats used to organize and process data; • functions, which are named procedures that perform a defined task; and • methods, which are programmed procedures that are defined as components of a parent class and are included in any instance of that class. Objects can do things and can have things done to them. For example, a function or method object can be programmed to modify the contents of a data structure or variable object.

Objects And Its Internal Representation In JavaScript: Objects, in JavaScript, is its most important data-type and forms the building blocks for modern JavaScript. These objects are quite different from JavaScript’s primitive data-types(Number, String, Boolean, null, undefined and symbol) in the sense that while these primitive data-types all store a single value each (depending on their types). Objects are more complex and each object may contain any combination of these primitive data-types as well as reference data-types. An object, is a reference data type. Variables that are assigned a reference value are given a reference or a pointer to that value. That reference or pointer points to the location in memory where the object is stored. The variables don’t actually store the value. Loosely speaking, objects in JavaScript may be defined as an unordered collection of related data, of primitive or reference types, in the form of “key: value” pairs. These keys can be variables or functions and are called properties and methods, respectively, in the context of an object. For Eg. If your object is a student, it will have properties like name, age, address, id, etc and methods like updateAddress, updateNam, etc. Objects and properties A JavaScript object has properties associated with it. A property of an object can be explained as a variable that is attached to the object. Object properties are basically the same as ordinary JavaScript variables, except for the attachment to objects. The properties of an object define the characteristics of the object. You access the properties of an object with a simple dot-notation: objectName.propertyName Like all JavaScript variables, both the object name (which could be a normal variable) and property name are case sensitive. You can define a property by assigning it a value. For example, let’s create an object named myCar and give it properties named make, model, and year as follows: var myCar = new Object(); myCar.make = 'Ford'; myCar.model = 'Mustang'; myCar.year = 1969; Unassigned properties of an object are undefined (and not null). myCar.color; // undefined Properties of JavaScript objects can also be accessed or set using a bracket notation (for more details see property accessors). Objects are sometimes called associative arrays, since each property is associated with a string value that can be used to access it. So, for example, you could access the properties of the myCar object as follows: myCar['make'] = 'Ford'; myCar['model'] = 'Mustang'; myCar['year'] = 1969; An object property name can be any valid JavaScript string, or anything that can be converted to a string, including the empty string. However, any property name that is not a valid JavaScript identifier (for example, a property name that has a space or a hyphen, or that starts with a number) can only be accessed using the square bracket notation. This notation is also very useful when property names are to be dynamically determined (when the property name is not determined until runtime). Examples are as follows: // four variables are created and assigned in a single go, // separated by commas var myObj = new Object(), str = 'myString', rand = Math.random(), obj = new Object(); myObj.type = 'Dot syntax'; myObj['date created'] = 'String with space'; myObj[str] = 'String value'; myObj[rand] = 'Random Number'; myObj[obj] = 'Object'; myObj[''] = 'Even an empty string';console.log(myObj); You can also access properties by using a string value that is stored in a variable: var propertyName = 'make'; myCar[propertyName] = 'Ford';propertyName = 'model'; myCar[propertyName] = 'Mustang'; You can use the bracket notation with for…in to iterate over all the enumerable properties of an object. To illustrate how this works, the following function displays the properties of the object when you pass the object and the object's name as arguments to the function: function showProps(obj, objName) { var result = ``; for (var i in obj) { // obj.hasOwnProperty() is used to filter out properties from the object's prototype chain if (obj.hasOwnProperty(i)) { result += ${objName}.${i} = ${obj[i]}\n; } } return result; } So, the function call showProps(myCar, "myCar") would return the following: myCar.make = Ford myCar.model = Mustang myCar.year = 1969 Creating Objects In JavaScript : Create JavaScript Object with Object Literal One of easiest way to create a javascript object is object literal, simply define the property and values inside curly braces as shown below let bike = {name: 'SuperSport', maker:'Ducati', engine:'937cc'}; Create JavaScript Object with Constructor Constructor is nothing but a function and with help of new keyword, constructor function allows to create multiple objects of same flavor as shown below function Vehicle(name, maker) { this.name = name; this.maker = maker; } let car1 = new Vehicle(’Fiesta’, 'Ford’); let car2 = new Vehicle(’Santa Fe’, 'Hyundai’) console.log(car1.name); //Output: Fiesta console.log(car2.name); //Output: Santa Fe Using the JavaScript Keyword new The following example also creates a new JavaScript object with four properties: Example var person = new Object(); person.firstName = “John”; person.lastName = “Doe”; person.age = 50; person.eyeColor = “blue”; Using the Object.create method Objects can also be created using the object.create() method. This method can be very useful, because it allows you to choose the prototype object for the object you want to create, without having to define a constructor function. // Animal properties and method encapsulation var Animal = { type: 'Invertebrates', // Default value of properties displayType: function() { // Method which will display type of Animal console.log(this.type); } }; // Create new animal type called animal1 var animal1 = Object.create(Animal); animal1.displayType(); // Output:Invertebrates // Create new animal type called Fishes var fish = Object.create(Animal); fish.type = 'Fishes'; fish.displayType(); // Output:Fishes