There are plenty of situations in which a fixed element (such as persistent navigation) could serve the owner’s business objectives and make the website more usable.

很多情况下，固定的元素（如固定不动的导航条）可以为目标客户更好服务，网站也更加实用。

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The home page release included new, persistent navigation at the top of the page, the Follow Bar at the bottom and a stack dedicated to personalizing your experience.

FORBES: Inside Forbes: 'Aha Moments' From Our New Home Page

The FORBES Follow Bar: Just two weeks ago, we added a new layer of persistent navigation to our article pages (see the graphic above or adjust your eyes downward to see it live).

FORBES: Inside Forbes: We're Breaking Free of the Time Warp the News Industry Is Trapped In