So apparently, after researching I found out that podcast means a recorded video that we can hear/view online and we can download it through digital devices such as PC/laptop. But if that's the case aren't all youtube videos considered a podcast? Or am I wrong?
Podcasts are often audio only.
They are similar to radio shows which talk about a certain topic for a certain amount of time.
Podcasts may be uploaded to YouTube as a video, but there is usually an audio-only version to accompany it.
I found this definition on dictionary.com:
A digital audio file made available on the Internet for downloading to a computer or mobile device, typically available as a series, new installments of which can be received by subscribers automatically.