It is important to understand the basic process involved with web applications.
First an HTTP Request is made to access a website. If the Internet DNS recognizes the web site it responds and an HTTP response is sent, downloading files from the host computer.
Code and images will be cached depending on the browser logic but essentially at this point everything is running on the client computer.
It should be evident that the faster your internet connection and the smaller your images and code are the faster the site will load.
Web content has grown from simple text to magazine quality presentation. Attempts have been made to create a more interactive dynamic web experience but up until the HTML5 standard they have been severely limited in favor of static content.