What is a Web Application?
We define a web application or web app is a client-server computer program in which the client (including the user interface and client-side logic) runs in a web browser. Common web applications include –
- Online retail sales
- Online auctions
- Instant messaging services and many other functions.
Web applications can be considered as a specific variant of client-server software where the client software is downloaded to the client machine when visiting the relevant web page, using standard procedures such as HTTP. Web applications are usually broken into logical chunks called “tiers”, where every tier is assigned a role.
- Web browser is the first tier (Presentation),
- An engine using some dynamic Web content technology like ASP, CGI, ColdFusion, Dart, JSP/Java, Node.js, PHP, Python or Ruby on Rails is the middle tier (Application logic),
- A database is the third tier (storage).
Such that the web browser sends requests to the middle tier, which services them by making queries and updates against the database and generates a user interface.
What is a Web Client-Server
Computers connected to the web are called clients and servers.
- Clients are the typical web user’s internet-connected devices and web-accessing software available on those devices like Firefox or Chrome.
- Servers are computers that store webpages, sites, or apps. Such that when a client device wants to access a webpage, a copy of the webpage is downloaded from the server onto the client machine to be displayed in the user’s web browser.