Tabs in Safari
This might seem like abit of an obvious one, but when you first buy your mac tabbed browsing isn’t enabled. To enable those tabs choose Preferences from the Safari menu and select the ‘Tab’ option, then click ‘Enable tabbed browsing’. You may want to have tabs open in the background, I do that and it’s brilliant when browsing Flickr explore & digg etc.
View more on Safari Tabbed Browsing.