In the current Web, most pages are either static files hosted on a server or dynamically generated by a server on a request. This is true for most server-side-rendered websites, for example, those written with PHP, Rails, or Django. Both of these techniques required no effort besides being displayed by the clients; therefore, they are called thin clients.

In modern web applications, the idea of the browser has moved from thin clients to fat clients. This means most of the website's logic resides on the client and the client asks for the data it needs.

Currently, this is mostly done via calls to an API server. This API server then returns data, commonly in JSON form, giving the client an easy way to handle it and use it appropriately.

Most modern websites are a mixture of thin and fat clients. Normal pages are server-side-rendered, where only some functionality, such as a chat box or news feed, is updated using API calls.

Meteor...