Theatre productions take place on a stage and have very different considerations than filmed performances. Performances will be in front of a live audience – in theatres and in studios for some television shows. Other performances do not have an audience and the feedback from these performances is not instant. A successful career in acting requires equal parts talent and practice with a bit of luck thrown in. Actors at work can be seen and heard everywhere: TV, the big screen, the theater, on the Internet, in videos and on podcasts. They portray characters from the past that have impacted history, and they portray characters that are destined to impact pop culture in the future. Some dabble in a variety of entertainment mediums, while some stick to the stage, use their voice to create new worlds or dedicate their lives to the silver screen. Some make up the cast of extras that round out a production, while some achieve levels of fame that makes them a household name.