Web App vs. Website
There is no strict demarcation between a web application and a website. Here are the directional definitions of those two concepts.
Website
A website typically refers to a set of web pages whose objective is to deliver information to website visitors. A website is typically designed and developed for one-way communication, and it is more static. Some examples are company websites, personal websites, or blogs. There may be some interactive functionalities, such as contact forms and membership logins; however, these simple functionalities are typically not enough to refer to a website as a web application.
Web Application
A web application refers to software or a platform that provides multiple functionalities through a web browser, and it provides more interactive and dynamic functionalities to users. Gmail is a clear example. It is beyond a website because Gmail provides multiple interactive functionalities through a web browser. Other examples are e-commerce platforms or online payment & banking platforms.
Typically, websites are developed largely with frontend coding (in HTML, CSS, or Javascript), while web applications typically require more effort in backend coding (in PHP, Python, or Ruby, for example) besides frontend coding.
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