Web browsers allow site visitors to save images to their computer. This is how web browsers are expected to work and most sites (even photography sites) make no attempt to stop this from happening.
To disable right clicking on your pages in many browsers (in order to prevent people from easily copying your text and pictures) paste the following into the "Footer Code" (NOT "footer message") box under the "settings" tab in the Search Engine Optimization (SEO) area of the editor:
<body oncontextmenu="return false;">
Save this change and it will be active once your site is Published. This option does not work on every web browser, but it does work on some of them.
But we must stress that it is virtually impossible to fully protect any image on the Internet. If someone wants it, they will find a way to access it, unfortunately. Pro users have the option to use password protected pages which offer the best form of protection, though visitors would then need a password to view the images.
Rather than protect images in this way, some photographers and others with online images choose to use graphics programs to add a watermark or stamp onto the online version of their photos. Although it does not prevent the photo from being downloaded, it does protect the photo in most cases since the watermark renders it useless.