Downloading Movie, Music And Other Illegal Files Can Cause:

Online movies and the movies found on the BitTorrent Network are illegal or known as pirated.

Pirated movies are of low Quality, does not provide extra functions like the DVD's we buy from the market.

Also if caught downloading pirated movies or storing it in any kind can lead to fine and imprisonment.

Many companies have started anti-piracy campaigns.

So, its better to stay away from the pirated movies and BUY ORIGINAL.

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Because:

Downloading Movie, Music And Other Illegal Files Can Cause:
-Infections That Slow, Corrupt and/or Damage Computer.
-Infections That Collect Personal Info About Yourself.
-Some Peer To Peer Programs (like LimeWire and FrostWire) including Torrents Can Contain Infections.
-Putting yourself at risk of being jailed.

Based on what I said above, with Illegal Files you have a high chance of someone getting at your personal info and/or infecting your computer.
As for jail time fortunately only on occasion people go there for piracy or stealing media files. Right now piracy is a high volume problem, I'm assuming thats why.

Keep It Legal And Your Computer Will Be Happy And Healthy. Keep It Legal And Your A Good Citizen, rather than a pirate.