Client-Side VS. Server-Side

Client-side means that the action takes place on the user’s (the client’s) computer.

Server-side means that the action takes place on a web server.

When we say action we mean all that work that programming languages do.

Almost every computer in the world understands one programming language: JavaScript. For this reason, most things that can be accomplished using JavaScript can be done without needing access to a web server.

Client-side vs. server-side describes where the action takes place (literally on your computer vs. a server). Frontend vs. backend refers to what kind of action is taking place.

Single-page application (SPA). vs. multiple-page application (MPA)

If you are thinking about creating your own application, you’ve probably heard that there are two main design patterns for web apps.

To decide what app model is better for you, you should follow content-first approach, which emphasizes the importance of putting your application content before everything else. That’s because content is the main reason for which users will or won’t use the application.

Single-Page Application

A single-page application is an app that works inside a browser and does not require page reloading during use. You are using this type of applications every day. These are, for instance: Gmail, Google Maps, Facebook or GitHub.

no page reloads, no extra wait time. It is just one web page that you visit which then loads all other content using JavaScript — which they heavily depend on.

SPA requests the markup and data independently and renders pages straight in the browser. We can do this thanks to the advanced JavaScript frameworks like AngularJS, Ember.js, Meteor.js, Knockout.js .
Single-page sites help keep the user in one, comfortable web space where content is presented to the user in a simple, easy and workable fashion.

Pros of the Single-Page Application:

SPA is fast, as most resources (HTML+CSS+Scripts) are only loaded once throughout the lifespan of application. Only data is transmitted back and forth.

https://medium.com/@NeotericEU/single-page-application-vs-multiple-page-application-2591588efe58