Seen those mosaic-like little squares around? (Such as the one to the right, on a UNICEF fundraising box.)

They're Microsoft Tags -- barcodes that you scan with a mobile device, such as a smartphone, to get more digital information on your device. They've been used by magazines to provide more content or promote giveaways, UNICEF for fundraising and art museums to provide more information on works on display.

Microsoft is a relatively new player in the field; its Microsoft Tag launched 18 months ago. [Update 12:52 p.m.: Clarification: Microsoft says Microsoft Tag launched in January 2009 and came out of beta in May 2010.]

In addition to the barcode, Microsoft Tag is also a platform that allows individuals and brands to create their own barcode tags, and includes a mobile app that allows users to scan the tags.

Today, Microsoft announced that in addition to supporting its own brand of barcodes, Microsoft Tag will also now support QR codes and Near Field Communications (NFC) capabilities. QR codes are among the most popular 2D barcodes today, while NFC is a newer technology that's not yet commonly used. (The most popular use for it presently is for making payments via smartphone.)

That means companies or individuals can create their own QR codes or Microsoft Tags using the Microsoft Tag Manager. It also means the Microsoft Tag mobile app will be able to scan QR codes and work with NFC technology.

In addition, Microsoft is releasing an API and Excel dashboard. The API will allow tag creators to take data about, for instance, how many people have scanned their tags, from Microsoft's systems and bring it into their own information systems. The Excel dashboard would allow tag creators to simply download such data in spreadsheet form.

Adweek is reporting that more magazines are using 2D barcodes such as QR codes and Microsoft Tags but that "questions still remain about its impact as an advertising tool."

According to Adweek:

GfK MRI Starch recently released data confirming that QR codes, or snap tags, are showing up more in magazine ads.

From January to August, MRI measured more than 72,000 ads. Five percent of them contained QR or snap codes, up from 1.3 percent in the second half of 2010. And the mere presence of the codes seems to get readers more involved with the ads containing them.

Microsoft says more than 200,000 accounts have been set up to create Microsoft tags -- most of those businesses.