On November 24, 2008, YouTube launched a new feature to allow users to upload and view widescreen high definition (HD) videos on the site. The YouTube video player was expanded to 960 pixels to more closely imitate widescreen viewing.YouTube Blog: Bigger Isn't Always Better... (November 24, 2008) Videos in the old 4:3 aspect ratio will continue to play in the larger format, but will have black bars on either side of the video to take up the extra space.Slashfilm: YouTube Goes Widescreen (November 24, 2008)
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"Over the years we've heard a lot of feedback from you about what you'd like to change about YouTube, and the size of our video player is always top of mind...We're expanding the width of the page to 960 pixels to better reflect the quality of the videos you create and the screens that you use to watch them. This new, wider player is in a widescreen aspect ratio which we hope will provide you with a cleaner, more powerful viewing experience."—YouTube Blog postYouTube Blog: Bigger Isn't Always Better... (November 24, 2008)