is it illegal to copy videos if you don't sell them?

Yes. but if you aren't selling them or doing anything with them but watching for personal use, there's -0- chance of being arrested or fined.

Depends on where you live. In some countries, you don't purchase a video, you purchase a license to use the footage for personal viewing. In that case, you can usually make a backup or archival copy as long as only one copy is in use at at time.

You can't make copies to give away or share though.

However the Digital Millenium Act makes it illegal in the US, If I understand it correctly (I am not a lawyer or an American.)

see www.chillingeffects.org for definitive answers to this and related internet era copyright issues.

Unless you copying falls under Fair Use exemptions, then yes, i tis a violation.

Even if you don't sell your copy, and making a backup copy is allowed under Fair Use, that may not make it kosher.

If your copy happens to be sitting on a p2p file server somewhere, being given away for free, then it is certainly a violation.

If you make a single copy and give it a away, to friend or family, it is not "Fair Use" as now you are distributing and competing with the copyright owner's Constitutionally granted monopoly to decide what to do with the work.

Dont listen to these people. I have an uncle that works in a copyright office. By law you are alloud one copy of the video. If you sell the video it is then illegall. If you give it away to a familly member its fine.

yes.