File Formats When streaming videos over the Internet you must decide to encode your videos in either MP4 or FLV formats. Most servers and players support both file formats. I personally recommend using MP4 because you get DVD quality videos at a much smaller file size. It also uses less CPU on client machines and it works on mobile phones. The downside to MP4 is that the videos will take longer to load than an FLV video. FFMPEG is a great free and very powerful encoder, but can be somewhat difficult to learn. It supports many popular video formats and has many options to configure. Bitrate is probably the most important factor in determining the quality and file size of your video. If your video contains lots of action and motion it will need to have a higher bitrate. Youtube encodes their normal videos at a bitrate of 200kbps and their high quality videos at 900kbps. Be wise in picking a bitrate because the higher it is the more likely users will experience streaming problems.
Many of you SEO fanatics may have realized that CodeIgniter is not very SEO-friendly out of the box. It auto generates URLs based on routes which are made up of a controller name and method name. For URLs to be considered SEO-friendly and be universally recognized by search engines, keywords must be separated by a dash. Many of you are thinking you will just go rename your controllers and methods with dashes. That would be nice and easy, but this is not a legal syntax and PHP will throw errors. There is the option to manually enter each route in your routes.php file, but this could be a serious beat down and come back to haunt you later on down the road.
Document Type Definitions (DTD), also known as DOCTYPES, are markup declarations of web standards designed to increase cross-browser compatibility. Unfortunately, there are many options to choose from and very few details on the web of what exactly they do and how they differ. As you may have noticed, most DTDs reference the website w3.org (W3Schools). This is because W3Schools is backed by a large community and is considered to lead the web development industry and define its standards.