Webpages often contain time-consuming programs that install software on your computer or show you ads. You can prevent pages from loading such content. Unfortunately, many beneficial features use the same technology, so if you block ads, you might also block the animation and interactivity that make webpages interesting.
To block certain types of content:
Choose Action menu > Preferences and click Security. (The Action menu is near the upper-right corner of the Safari window, and looks like a gear.)
In the “Web content” section, select or deselect types of content you want to block or enable. For an explanation of the options, click the Help button (looks like a question mark).