Support for video and audio file formats varies across browsers.
These video formats are:

• Theora (.ogg, .ogv) – The free and open source container format from the Xiph.org foundation, for the open source Theora codec. Results in lower quality than H.264 and uses the application/ogg MIME type and the video/ogg video attribute type
• MP4/ H.268 (.m4v) – The compressed container format for the H.264 codec, with high definition support and uses video/mpeg MIME type and the video/mp4 video attribute type
• WebM (.webm) – Open source container format supported by Mozilla, Opera, Adobe, and Google., compressed by VP8 codec and uses the video/webm MIME type and the video/webm video attribute type

A standard video format has not yet emerged.   Thus, it is important to know what video formats the various web browsers handle in order that as many users as possible can see your content.

Here is a chart of what browsers support what file formats:

Source devcurry.com

1. Placing Distracting Elements Like Animation or Flashing Items Near Important Content

Distracting elements can draw your viewer’s eye away from your content and make it impossible for them to take away your intended information.

2. Using Little Text Boxes With Scroll Bars To Deliver Content

This one is self explanatory if you have ever visited a site that crams all of its content into tiny boxes. After a few seconds of scrolling at most, many visitors will move on in search of an easier-to-read choice.

3. Choosing Overly Busy Or Colorful Backgrounds

A background that makes it difficult or impossible to read your content will not only drive visitors away but will also give them a headache.

4. Using Very Long Introductions or Animations

This goes back to the short attention span issue. If your intro is longer than a few seconds, many of your visitors will lose interest and move on to another site that delivers content more quickly.

5. Taking Minimalism To The Extreme

A minimalist approach can create a professional, polished look but if it is taken too far your website will appear boring and amateurish.

6. Using Mismatched Graphics

Choose graphics that follow a theme. Using graphics that span time periods, color schemes, or styles detracts from your content and your site’s credibility.

7. Including Too Few Graphics

Very long units of text unbroken by graphics can be as unappealing as too many graphics. A quality website has a nice balance of text, graphics, and other utilities to keep viewers interested and involved.

8. Choosing Graphics That Are Completely Unrelated To Your Content

There are many pitfalls for anyone seeking to have a website developed. Your website is part of your “brand” and is usually the first impression that a prospective client, fan, or recording label has of you and your brand.  Thus, a properly designed website must go beyond coding, beyond the friend of a friend who says they develop websites, or the one person operations that hangs a “design shingle” on their front porch.

Graphic design must play a fundamental part of any web design. It not only is the creative spirit of your site but is critical to the overall branding strategy of a product, business or recording artist. Graphic Design  encompasses everything from back ground images, banners and button controls to color scheme, text style, and graphics.

An ideal graphic design can give a huge boost to your website by increasing its visual appeal, professionalism, brand value and usability.

Visual appeal is vital to web design because it promotes communication of ideas to your viewers by stimulating aesthetic senses and increasing a feeling of connection.

Effective graphic design also lends an air of professionalism to your site. Visitors are more likely to consider your content worthy of reading if the overall website gives an appearance of authority on the subject.

Finally, good graphic design increases the usability of your site. Web visitors often have little patience for complex or confusing sites and will move on fairly quickly. You can encourage viewers to stay on your site by using graphic design to keep navigation simple, making sure your graphics are content appropriate, and choosing eye-pleasing colors and text styles.

So many businesses out there set up a website and then think, “There, that’s done with” and never bother to re-evaluate their website’s design or position in the marketplace.

But looking at a website as a static, unchanging bit of advertising will put you at a disadvantage sooner or later.

It’s much better to look at your website as a constantly-updating and evolving part of your online presence.

Your design should be updated regularly to reflect new developments both in your business (or personal development if it’s a personal site) and should be redesigned thoroughly whenever necessary. Use our guide below to help you along the path of a redesign.

How to Know if Your Site Needs a Redesign

It Uses Outdated Technologies and Techniques

If your site uses technologies or design techniques that have become dated, it’s probably time for a redesign. While deprecated code is the most obvious of these, there are a lot of other things to watch out for, including:

• Frames
  While the occasional iFrame might not be anything to worry about (and are often used for widgets, affiliate programs, or advertising), if your site makes use of frames for a major portion of its design, it is definitely time for a redesign. Frames have been outdated since around 2000. Get rid of them.
• Intro Pages
  Intro pages were all the rage in the early 2000s. Most used Flash and/or audio content. While intro pages aren’t necessarily a completely outdated design technique, it’s becoming more rare to see them. If your site has a lengthy Flash intro, it’s probably time for a redesign.
• Outdated Content
  Modern websites need to be updated on a constant basis. Even if you have a “static” site, you still need to make sure the content on it stays current. Many older sites weren’t built on a content management system and can be a pain to update, especially for people who aren’t comfortable with coding. If your site isn’t built on a CMS (like Archimedia Studios’  iCMS), it’s probably time for a redesign.
• Your Site is Entirely Flash
  Most sites nowadays are not built entirely with Flash. Even those that appear to be, often have content pulled in from XML files, instead of being hard-coded into the Flash files. If your site was built with only Flash, it’s likely you’re suffering in the usability and SEO departments. Consider a redesign.
• Tables
  Tables were in fashion a few years ago in website design, but tables were never really meant for laying out the design of a site; they were intended for formatting data. Designers just figured they were handy for creating complex website designs. If your current site is designed using tables, it’s time for a redesign.
• Trendy Design Elements
  If your site was designed with trendy elements (such as Web 2.0 glossy buttons), it’s probably a good idea to redesign it as soon as those trends start to fade. Don’t wait until you’re the last site around using one trend or another. Stay ahead of the curve and redesign while it still looks at least somewhat fresh. Also, consider steering clear of trendy elements, or at least incorporate them in ways that will be easy to change in six months.