20 podcasts that will make you smarter

Pete Souza/White House

President Barack Obama speaks with Marc Maron in Maron's garage for an episode of the "WTF" podcast.

The past couple years have been huge for podcasts.

Episodes of true crime series "Serial" were downloaded more than 80 million times, President Barack Obama visited comedian Marc Maron's garage for his "WTF" podcast, and leading Democratic presidential candidate Hillary Clinton had a candid chat with "Another Round" hosts Heben Nigatu and Tracy Clayton.

With new series coming out each week, it can be difficult to determine which are actually worth your time, but we've got you covered if you're looking to learn something new.

Here are our top picks for stretching your brain during your next commute, workout, or laundry run.