1) What is Meteor or MeteorJS?

Meteor is a JavaScript platform used for developing web and mobile applications. Applications develop using Meteor framework supports different platforms (like windows, android, ios). Meteor includes a key set of technologies such as Node.js and general JavaScript community.

2) What are the features of Meteor?

Web and mobile: Meteor provide platform for developing Android, IOS and Web apps.
Packages: Meteor support huge number of packages that are easy to install and use.
Universal Apps: The same code is used for mobile device and web browser.
Meteor Galaxy: Meteor offers Meteor Galaxy Cloud service for app development.

3) What are the advantages of Meteor?

Meteor apps are by default real time. The data in the templates automatically gets updated, as soon as changes to the data are made.
Coding is very simple and beginner friendly.
The development process is highly simplified as frontend, backend and database all uses one language i.e. JavaScript.

4) What are the disadvantages of Meteor?

Meteor is not very much suitable for large and complex application.
The Meteor API is rapidly changing, so each new version may bring breaking changes.
Due to newer in industry there are not as many hosting services available for Meteor apps yet (Meteor 1.0 version).

5) What are the tags used in Meteor template?

Meteor template uses three important tags. These are head, body and template. Head and body tag has same function as in regular HTML, but template tag is used to connect HTML to JavaScript.

<head>  
   <title> </title>  
</head>  
 <body>      
</body>  
 <template name = "">   
</template>

6) Which database is supported by Meteor?

Meteor (version 1.5) currently support MongoDB database. Meteor API is rapidly changing, so each new version may bring breaking changes.

7) How Meteor uses MongoDB collections? And how data are saved?

Following line of code create connection with Meteor with MongoDB:

MyCollection = new Mongo.Collection('myCollection');  
var myData = {  
   key1: "value 1...",  
   key2: "value 2..."  
}  
MyCollection.insert(myData);

8) Why developers choose Meteor for app development?

Meteor uses JavaScript language for front end as well as backend development. It makes dramatically fast development time and great for rapid prototyping.

9) How can Meteor apps compile?

Meteor apps compile by using Apache Cordova. So we don't have to create separate codebases for Android and iOS. This results in high-quality apps that run a mix of web and native code.

10) What is session and how session can be created in Meteor?

Session is used to save data while app is in use. The session data will be deleted while user leaves the app. In Meteor session are created by using Session.set() method. Once the session data is set, it can return using Session.get() method.

11) What is tracker in Meteor?

Tracker is a small library that is used for auto update templates once the session data has changed. Tracker.autorun() method is used for tracking on session.

var data = 0  
   Session.set('sessionData', data);  
   Tracker.autorun(function () {  
      var sessionValue = Session.get('sessionData');  
      console.log(sessionValue)  
   });  

   Template.myTemplate.events({  
      'click #myButton': function() {  
         Session.set('sessionData', data++);  
      }  
   });

12) How can Meteor provide security for mobile or web application?

Meteor offers large number of packages for application development. Developer need to remove some insecure or less secure packages while development. Another way to provide security of application is that, creating your methods on the server. This can be done by using the Meteor.methods() on the server and Meteor.call() on the client.

13) What is Blaze in Meteor?

Blaze is a Meteor package used for building live reactive templates.

14) What is Meteor EJSON?

EJSON is an extension of JSON syntax that supports Date and Binary types. The date and binary can be deserialize using the parse method. For example:

if (Meteor.isClient) {  
   var ejsonDate = '{"$date": 1455029631493}';  
   var myDate = EJSON.parse(ejsonDate);  
   console.log(myDate);  
}

15) How and where to deploy Meteor app?

Meteor provides its own server (free) to deploy and test your application with command "meteor deploy appname". If you want to deploy application on your own server and domain, you will need VPS (Virtual Private Server) or cloud hosting like Heroku or Modulus.

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