Most of the end user response time is spent on downloading images, scripts, Flash, components, etc. This might be the problem while dealing with the Rich Interface websites in which developer require number of different images, scripts and CSS files. First of all you reduce the number of request generating from your web page.
Here are some Tips for that:
- Combine CSS and JS files. Combine files is the way to reduce the number of HTTP request by combining all scripts and CSS files. Combining stylesheets and script files into single fie is the difficult and lengthy task for larger application but it will surely give the positive results when done.
- CSS Sprites. CSS Sprites is the method of reducing the background image requests from your site. All you have to do is to include various background images into one and use the background- image and background-position CSS property to display the required portion of the image.
- Image maps combine multiple images into a single image. The overall size is about the same, but reducing the number of HTTP requests speeds up the page. Image maps only work if the images are contiguous in the page, such as a navigation bar. Defining the coordinates of image maps can be tedious and error prone. Using image maps for navigation is not accessible too, so it’s not recommended.
Reducing the number of HTTP request is the Key Step to start optimization. Most of the users are coming with empty cache to you website. So it’s better to improve the loading time of the site for first time.
Source : Yahoo Tips