A web-based application is any program that runs within a web browser and relies on a client-server model. It is coded using browser-supported languages like HTML, CSS, and JavaScript. Some key advantages are that web apps do not require installation, can be accessed from any device with a browser, and are easier to update centrally. Common examples include webmail, e-commerce sites, and wikis. In contrast, a windows-based or "thick client" application runs locally on a user's machine within a windows environment and may have more robust features but is only compatible with windows and requires installation.