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 makes webpages interesting.
Choose Safari > Preferences.
Click Security.
In the Web Content section, check or uncheck types of content you want to block or enable. Click the Help (question mark) button to see an explanation of the options.