How to reduce wp site loading time?

There are some tips to reduce the wordpress site loading time. Such as reducing image size, reduce database loading time, javascript file and so on. But I cant understand how to do this?

I recommend the W3 Total Cache plugin: http://wordpress.org/extend/plugins/w3-total-cache/
You can use it to generate static HTML pages of any part of your site, which can then be served to your users, thus dramatically decreasing load time.
You can also use it to minify your HTML, CSS and JavaScript, or to cache database requests.
If your site has enough users to warrant using a CDN, this plugin will help you with that, too.
And the best part … it’s free!

Apart from that jQuery Image Lazy Load WP, might be worth a look: http://wordpress.org/extend/plugins/jquery-image-lazy-loading/
This ensures that images on your site aren’t loaded till the user needs them.

Hope that helps.

I would also suggest (although this isn’t really directly related to WordPress) installing the YSlow FireBug add-on (Firefox-only) and letting it analyze your site and tell you what to do to speed it up.

Also, if your theme / blog posts make heavy use of images, consider optimizing them (without quality loss) through a service such as Yahoo! SmushIt.

Thanks for those tips… my site was loading slower than molasses in january and i was going to start investigating in getting a dedicated server to solve the issue.

There are various techniques and tips to reduce the Wordpress site loading time. Normally we always consider the website loading speed, trying to use a small size image and graphic as well as avoiding the use of unnecessary image and graphics to maintain the website performance and improve loading speed. Wordpress also provides several inbuilt plugin which will assist you in improving the website loading speed. Some useful Wordpress Plug-in are WP Minify, W3 Total cache, WP Database Optimizer and WP Smush.it. You can check the web page loading speed through this tool http://tools.pingdom.com/fpt/.

there are many technicians to reduce word press loading site you can follow some instruction like HTML Code Optimization, Focus on Content, Choose correct format for images, Analyze W3C standard and Load time regular.