Slogan vs Tagline

So, our team at Instant Logo Design - http://instantlogodesign.com/ just posted a blog that tackles about 'Slogan.' However, I just saw a thread at an external website that talks about Taglines. Now, I'm not sure how different they are from one another, but does anybody know their distinct differences? I know they are used interchangeably, but in simple terms, how can you differentiate them?