Have you ever asked your web developer to open a link in a new tab or window? Generally, this is accomplished by adding a target="_blank" attribute to a link. Let’s consider the usability implications.

The rationale is almost always founded in a desire to keep the audience engaged with your content longer, or a concern about usability (for example, keeping the reader losing his or her bearings). The overwhelming finding from user experience researchers*, however, is that new windows/tabs should be avoided when simply opening new web pages. However, there are some appropriate use cases: opening a non-HTML document (web page) like a large image, video, audio, or other media, or to avoid interrupting an important linear process like a checkout. Even with these exceptions, however, there are  friendlier alternatives like tool-tips and lightboxes.

In fact, the target="" attribute was actually deprecated (being phased out) from the HTML specifications until HTML5. As of HTML5, the W3C guidelines stipulate that it is no longer deprecated because it is deemed “useful in Web applications, e.g. in conjunction with iframe.”

Here are our recommended best practices:

For internal links: Internal pages should never be forced to open in their own window or tab.

For external links: If you want to warn your audience that they will be leaving your site, use a visual cue such as a wikipedia-style box-arrow .

For media, aside/meta information, or contextual help: Use another technique, such as rich tooltips, overlaying light boxes, or other modal boxes.

In short, forcing the visitor to open another tab or window is disruptive. Your audience has the tools they need to open a new window if they wish to, and those confused by window management will also be confused by an imposed new window / tab.

*Sources:
Smashing Magazine: Should Links Open in New Windows?
tribalogic; Why Opening Links in a New Window is Wrong
StackExchange UX: Is it okay to open a help link in a new window?