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An article about webdesign

This small guide is about to show you how many things you can do wrong when creating a website.
It's rather a "top ten mistakes of webdesign"-list
[Update] Now it's a "top eleven mistakes of webdesign"-list

1. Advertisements

Your website is not the Times Square. NEVER add ANY kind of flickering, blinking, always-on-top advertisements on your website. They are annoying, look incompetent, and will only result in distracting the user from your site. Furthermore, they can ruin the user's experience of the webdesign, because the viewer can not fixate his eyes on the main design and content, if there are flickering ads flying through the screen all the time.
Don't even add banners that only LOOK like advertisement, even if they aren't.

By the way, web advertisements don't work. Have you ever clicked on one out of interest?

2. Sounds (often used within ads)

Someone who is browsing the web isn't looking for a disco-like sound theatre. Your website should not play loud sound unless the user has selected to play it. Of course, nice sounds give websites a special touch and atmosphere, but nobody wants to blow up his ears or his soundsystem, thus you should set the default volume to 0, or at least very low.
Because you will not use ads anymore from now on, I don't have to write that you should remove ads which include sound.

3. Popup windows

Everyone knows them, everyone hates them.
Actually, those silly ad-popups have ruined the users webbrowsing experience also on good sites, which might use popups to open a search window for example.
Many people will close the window even before it has loaded at all, or use a popup blocker instead. But even "good" popups are not always nice, especially on small screens, where the main window is already in fullscreen, and the user will most likely not notice any windows popping up in the background. Also, a new window interrupts the browsing flow, because you can't use the "back"-button to return to the previous page, which will mostly end up in confusing the user, who will surely close the wrong window every now and then. Everyone who wants to have a new window, can and will open one himself whenever he wants to. Of course, you can ask the user if he wants to open a link in a new window, but always keep the choice to stay in the actual window (make sure that this works cross-browser).

4. Delaying or blocking the "back"-button

This is not the way to keep a user on your site, because you can't block the x in the top right of the window. :P I would recommend that you attract the user with good and interesting content, and he will surely come back on his own, instead of building a one-way jail around your page.

5. Dead links

It just sucks when you click a link and get a 404-not found error. The user can't use what is not there, thus I would recommend to check all links regularly.
Changing urls all the time is equivalent with a dead link, unless you keep both urls active for a while, and notify the user of a redirection taking place in the background. Despites, you will still lose many visitors coming from links on other sites, and hurt your referrals with dead links. In addition to that, you should always keep archives, because this will avoid dead links, and the user will not be searching for things which dont exist anymore.
[Update] However, there is a very nice solution that can help the user to find a file he needs.
If you can edit your 404-Error file (google for "htaccess" and you will find the solution, or wait for my totorial ;)), you could create a php file that searches any files which are more or less equal. Of course, you cant compare the content of the files which don't exist, but you can try to find the file in a different folder or look for equal filenames, or you can ask archive.org.
Another thing that has been annoying me in the last couple of days was the well-known "no direct linking allowed", which blocks access to a file under special circumstances, such as the referrer domain not being identical with the one of the webspace hosting the image.
I'm using the google image search quite often, and mostly the cool files are blocked, resulting in me muckraking through the page to find it.
I would prefer to be informed about the hoster, instead of running against closed doors. A message like "file kindly hosted by XYZ" is much nicer than a more or less dead link, as both the user and the hoster will be happy in the end! The visitor finds what he wants, and the hoster will be delighted to have a positive advertisement which will be well-recieved as it has actually helped the user by hosting the file, instead of annoying him.
I hope I don't have to mention that this advertisement should be a simple and plain text to ensure that it's actually read by the visitors. People will be very thankful when you help them, so why not do so if you can even advertise with this?

6. Long loading times

If the website is very slow, it will challenge the user's patience and at some point, he will just leave. Get a faster webserver or optimize your code. Using Gzip can be nice, too. You can easily test the speed and state of optimization here:
website speed report - by WebsiteOptimization.com
GZIP website compression tester - enter your URL and find out if the site is compressed. If it isn't the report gives you an idea of how much smaller the file would be if you used compression.

7. Graphics: Images

Many images will overload the page and increase the loading time and traffic. No images can result in an empty looking page, but it doesn't have to. CSS code is very powerful, but it can also make things complicated. Sometimes you can use a simple gif instread of compex table arrangements or CSS-aligned objects.
I don't want to write too much about graphical webdesign details, but the most important thing is that your website looks clean and provides a good overview, resulting in a satisfied user who will find what he needs.

8. Graphics: Fonts

Some people seem to be confident of websites using many different fonts being cool, or they just want to show how many fonts they have... Seriously, using more then 2 or 3 fonts looks really silly. You should try to use max. 2 fonts, and only a very small amout of different sizes.
Also, use font decorations (bold, italic, etc.) with caution, and never underline something unless it's obvious that it's not a link.
[Update]Another very important thing, which is forgotten very often, is that the user will likely not have the same default settings as the developer/designer of a website. This means that the user might have set the background color to black, and thus your website using a Cascading Style Sheet which only sets the font color to black, will be unreadable! This is, of course, the extreme case, but there are many websites out there which look weird just because of the font face or color not being the same as intended.
To avoid this, all you have to do is define ALL colors, and please do not use the font tag, as it's incompatibilities are endless. CSS is definately the way to go! You should at least define the background- and font colors for the following tagnames: a:link, a:visited, a:hover, a:active, html, body, td.

9. Using Windows-GUI elements that don't work like the ones in Windows (Flash mostly)

Consistency is one of the most powerful usability principles. When things always behave the same, users don't have to worry what will happen, because they KNOW what will happen. For example, ad banners often use select elements, but they are just part of an image, which will only direct you to the website of the advertiser.
Also, the Windows user knows that he can check more items when using square checkboxes, and only one item if they are round.
The last example will usually not be caused by simple html code, but I have seen many flash websites which seem to work without any logical sense in their navigation. In addition to that, you can often not select text on flash websites, though the user may want to.
Would you open notebad and start to typewrite a whole site from screen to screen?
[Update2] Another Flash-specific problem is the contextmenu which usually appears when you right-click on a Flash-element which will block the brower context menu, and a Flash-specific one without any useful functions will show up, resulting in breaking commands like "Open in a new window" or "Open in a new tab".
This is one the major reasons why the page you are viewing right now was developed with classic HTML and Javascript.

10. Never use pdf files to view them online

PDF files will load extremely slow, especcially when there are many different ones, and the user has to open a few files until he finds the info he was looking for. Of course pdf files are not bad - actually they are very good - but only if they are downladed on the user's disk.

11. Avoid abbreviations

Don't write what the user will not understand. Not everyone knows the meaning of common abbreviations, and he will most likely not understand parts of the website. I am now especially thinking of common chat words like "lol", "brb", etc.
Never use abbreviations in headlines.
post: webdesign