Following an established standard for your website's page size keeps site visitors from having to scroll to read your information. If you determine the basic dimensions of your website before publishing it, you can eliminate this concern.
Most websites range from 720 to 1,000 pixels wide. If a website visitor has his monitor set up to 800 pixels or more and the page is wider than 720 pixels, he will have to scroll the screen to the right in order to show all of the information. Forcing a visitor to scroll either left or right reduces the likelihood that he will continue to use your website.
The usual computer monitor resolution will show roughly 600 pixels before a viewer has to scroll down. Though some website owners may argue that they want all information on the page without a viewer having to scroll at all, most sites will simply make sure they list the most important information within that 600 pixel area.
A single page on a website that exceeds 70 kilobytes will take longer to download. Website designers can modify the "weight" of a page if they know how their viewers are accessing the website, such as through a cable modem or wireless network.
Most websites align to the center of the page, though some may align their information on the left side of the page. Center aligning reduces the amount of visual white space on the screen for those viewers who are using larger monitors.