Understanding screen resolution and how it relates to web design
Every web design studio that has ever existed has at one time or another been faced with these questions from clients: "why doesn't the page fill the screen?" and "why does it fill too much of the screen?", and the classic "why do I have to scroll down to see everything?".
They are all fair questions and deserve an honest answer, but before this can be explained you will need a quick primer on what 'screen resolution' is.
What is screen resolution?
When we talk about screen resolution, we are talking about the number of horizontal and vertical pixels your screen is capable of displaying. You may have heard someone say something to the effect of "I'm running my screen at 1280 x 768" - that means the screen is 1280 pixels across the horizontal axis and 768 pixels along the vertical. Higher screen resolutions are able to display more of a web page before having to scroll down.
One thing to remember about screen resolution is that its never constant, which means web designers have to commit to a certain set up rules in order to make web pages display nicely on monitors with varying resolutions. In an ideal world everyone would use the same resolution, but the reality is monitors come in different shapes and sizes and have different specs.
As a result, these days web designers will design a web site to fit monitors running at a very minimum of 1024 x 768, where only the width (1024) is of any real concern. Web pages higher than 768 simply mean the user will have to scroll down to see what's below.
As an example, here is how much screen real estate a typical web page (designed to fit a 1024 wide screen resolution) will have at varying resolutions:
As you can see, higher resolutions mean more of the page is visible before having to scroll down. In the case of 800 x 600 though the user would also have to scroll horizontally, as that resolution is lower than what the web page was designed for (1024 wide).
Why you have to scroll down: debunking the 'above the fold' myth
Even if you've not heard the term 'above the fold' you probably already know what it means. The term is a throwback to the ancient physial news format (remember that?), when a newspaper was folded in half the content visible on the front page above where it was folded was considered most important.
In web design this refers to how much of the page is visible before the user scrolls down. In other words, everything you see is considered to be 'above the fold'.
The problem with this idea as demonstrated earlier is that the fold is not a constant - it will simply be what ever screen resolution the user is running - which means it could be any value.
And if it's not a constant, it's impossible to design a web page that makes all the 'important' information above the fold on all screen resolutions.
There has been much debate over the years about the significance of the fold, but many studies have since concluded it to be an unimportant factor in web design and more importantly, a non issue for usability.
Conclusions
At the end of the day, there's nothing to be concerned about when users have to scroll down to see certain parts of your web page. In every web page scrolling is inevitable, and studies have shown that scrolling is not only instinctive to an overwhelming majority of users and just as easy as a click, but in most cases it's expected.