What's the difference between a Psychopath, a Sociopath and a Narcissist?

All Mighty... First of all - I do think that many of us are throwing around with those terms these days! And that these terms are misunderstood. So what could be the reason? Maybe some movies like - The Silence of the Lambs with the character Hannibal Lecter - are so formative that you change your perception!

And Second - 𝐑𝐚𝐦𝐚𝐧𝐢 𝐃𝐞𝐫𝐯𝐢𝐬𝐮𝐥𝐚, 𝐏𝐡𝐃 made this very simple and understandable in a video: 

'... 𝐄𝐯𝐞𝐫𝐲 𝐏𝐬𝐲𝐜𝐡𝐨𝐩𝐚𝐭𝐡 𝐢𝐬 𝐍𝐚𝐫𝐜𝐢𝐬𝐬𝐢𝐬𝐭𝐢𝐜 𝐛𝐮𝐭 𝐧𝐨𝐭 𝐞𝐯𝐞𝐫𝐲 𝐍𝐚𝐫𝐜𝐢𝐬𝐬𝐢𝐬𝐭 𝐢𝐬 𝐏𝐬𝐲𝐜𝐡𝐨𝐩𝐚𝐭𝐡𝐢𝐜. .... 𝐀 𝐏𝐬𝐲𝐜𝐡𝐨𝐩𝐚𝐭𝐡 𝐢𝐬 𝐛𝐨𝐫𝐧 𝐚𝐧𝐝 𝐚 𝐒𝐨𝐳𝐢𝐨𝐩𝐚𝐭𝐡 𝐢𝐬 𝐦𝐚𝐝𝐞! ...'