With nearly 8 years of video uploaded and 3 billion views logged every day on YouTube, it's clear you like to watch and share YouTube videos. While you're watching your favorite or new videos, we at the 'Tube are obsessing night and day over how those videos are presented. Our team is constantly experimenting, tweaking and playing with new ways to make your experience exactly what you're looking for. Today,

To kick off the 2011 graduation season in the United States, we featured some inspiring commencement speeches available on YouTube. Since then, many new addresses have been uploaded, including Amy Poehler's speech at Harvard Class Day, Denzel Washington's address at the University of Pennsylvania, and First Lady Michelle Obama's ) Part 1 and Part 2 ( at Spellman College. While you can spend hours watching these and other addresses on YouTube,

Across the country, students are throwing on caps and gowns and marching across graduation stages to collect well-deserved diplomas. As important to a graduation ceremony as "Pomp and Circumstance" , commencement addresses have become a central component of the big day. From celebrities to humanitarians to heads of state, colleges and universities are putting a big focus on speakers that will inspire and entertain those gathered for the occasion. Before online video,

In honor of National Teacher Day in the U.S. we've asked The Teaching Channel , one of our YouTube EDU partners, to help celebrate the educators in our lives. While National Teacher Day in the U.S. is an important reminder of the invaluable contributions made by teachers, we celebrate great teaching everyday at Teaching Channel because there is so much to learn from inspiring teachers. Who hasn't had that one teacher whom you will always remember?