A basic introduction on how to create a playlist in Spotify.
First, what's a playlist? A playlist is a saved collection of tracks you have individually chosen that you may listen to continuously and add to/delete from as you so desire. As it linked to your account, you have total control over it even if you share it with other people. People that are new to Spotify sometimes confuse a playlist with the play queue. The play queue is different from a playlist in that it is only available during the current session and is not saved once you logout from that given session.
On to it...