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I have a problem, something I'm sure a lot of video sharing companies might have. I want to start a small business by offering online video-based training courses on Microsoft Office and other office software in my town on my native language. The problem is, I'm planning to start offering cheap suscriptions for all-access to all the videos, maybe $for 5 dollars a month to get more people interested...however, I know my target audience, and I'm sure they will quickly resort to wanting to download the videos to stop paying, and who knows, maybe even share them on some site and make them public ruining my business...
My question is, is there a video format, or a way to embed, I don't know, a video file so that it cannot be downloaded for offline playback? Maybe using flash files in some remote server? I don't know...I just need a way to play videos on a web browser, that won't allow any form of downloading for offline playback and distribution. Please help guys, I'm kid of struggling to make enough money to pay for college already.
 Thanks for all the information everyone...It seems there is no right answer for this, so let me rephrase the problem.
I'm going to be dealing with people with little to no knowledge of advanced computer usage. My target audience consists of 18-23 year old college students that only use their computers for Facebook, playing candy crush, watching youtube videos and doing their homework. I know most of them are now aware of how to download videos from the internet, but their knowledge is very limited (and by that, I mean sites like KEEPVID.COM or youtube-mp3.org). Most don't even know screen capture software exists, or how to get it, so I'm hoping to use that "naive" characteristic to some use.
So ok. I CAN'T stop my videos from being downloaded, but is there a way to, as I said, make it harder, say...stop sites that download the actual video file hosted/embedded? I don't mind if you can still download the video with some tricks, I just wan't my target audience to have a hard time figuring it out. Right answer goes to the most useful answer, since there is no right answer.