We have had sound since Radio back in the 1920s, the podcast is the modern equivalent of this, with the ability to listen in your own time to topics of interest to you. Something I have been listening to on and off is the EdTech Podcast by Sophie Bailey, this is one of the podcasts (on the platform libsyn.com) from a few weeks back.

Podcasts such as this are very useful to Learning Technology and/or Academic Development professionals as they give bitesize continuous professional development (CPD) on a variety of topics to keep you updated on this fast paced area.