If you haven't started paying attention to the world of podcasting, now is the time to start. The medium has existed since around 2004 back in the early days of the iPod. It took until about 2014 for podcasting to enter the national conversation, with the boom being accredited to the runaway success of the true crime podcast Serial. It's continued to mature, with experimentation with release schedules and methods, show formats, and show subjects. It's also continued to grow, becoming more popular than ever with 44 percent of the United States population having listened to a podcast and with over $220 million dollars a year spent on podcast advertising.