Building High Performance HTML Pages

Building High Performance HTML Pages

DEFER Your Scripts
indicate to Internet Explorer 4.0 or later that the script tag contains no immediately executing code that impacts the document before the load event fires. Combined with the SRC attribute, the DEFER attribute can be used on a script tag to indicate to Internet Explorer that the associated code should be downloaded in the background while the rest of the components of the page are downloaded and parsed.
Scope Your Object References Wisely
JScript and VBScript are interpreted languages. Because all the work is done at execution time, relative to compiled languages, these languages are slow. Within a script, every reference to an object amounts to two calls from the scripting engine to the DHTML Object Model.
Use Fixed-Size Tables
Set the table-layout CSS attribute to fixed on the table.
Explicitly define col objects for each column.
Set the WIDTH attribute on each col.
Close Your Tags
Unlike XML, HTML has the notion of implicitly closed tags. This includes frame, img, li, and p. If you don't close these tags, Internet Explorer renders your pages just fine. If you do close your tags, Internet Explorer will render your pages even faster.
Leverage the HTTP Expires Header
Browsers typically store the resource along with the expiry information in a local cache. On subsequent user requests for the same resource, the browser can first compare the current time and the expires time stamp. If the time stamp indicates a time in the future, the browser may simply load the resource from the cache rather than retrieving the resource from the server.