how do i prevent people from stealing my pictures with the right mouse click?

check out www.javascriptsource.com , they have a number of "no right click" scripts there

Its virtually impossible to prevent users to copy an image which you posted on your website.

1. Theres a print screen function which allowed a user to grab a screenshot from their monitor. (Even if your image is in a flash file, theres no escaping this one)

2. The user (if he knows something about computers) can look at those html sources and go directly to the location of the file and save the file on his local hard disk.

3. Javascripts that prevents user on using right-click provides a false-sense of security. (well, it works on some people who doesn't know any trick aside from right-clicking the image and saving it)

One thing that will definitely work and prevent others to copy your image is: DO NOT POST YOUR IMAGE OVER THE NET!

I am assuming you are asking how you can prevent people from taking picture from a website.

It depends on where did host these image, if you have your own website, or blog, you can probably included a small javascript program on the code of the website that popup a prompt to prevent people use the right click and save image feature.

put a copyright notice and make sure you own all the rights to everything.
Then who cares who steals them as they cant use them for anything.
If you were really worried and this was a picture selling online store for example i would put a matermark over the image so that you can still see the image but it is completely ruined by a "preview" sign.
As others have said it is almost impossible to stop people from stealing pictures as even if they cant right click there is always the printscreen option.

It is virtually difficult to prevent that, even without the mouse, Alt + Prt Sc can also be used to copy those photos.

check out this page for coding
http://www.hypergurl.com/norightclick.html