Furthermore, if you find somebody whose tastes you like, you can “follow” her (either one board or all of her boards). Her stuff shows up on your Pinterest home page in real time, as she pins stuff.

You can also set up collaborative pinboards, where people you approve can contribute to one of your boards. That’s a sensational feature when your friends or your family members are trying to brainstorm ideas for a wedding, vacation, baby shower or renovation. Everybody chimes in with ideas, comments and votes on the submissions so far. You’re spared an awful lot of “What do you guys think of this?” e-mails.

In the end, three things make Pinterest so refreshing. First, it’s pure, uncluttered and non-blinky. There are no ads, scrolling columns or pop-up anything.

(The company doesn’t say it’s still figuring out ways to make money from this thing, but clever bloggers have already discovered one way. You know how Amazon.com offers an “affiliate program?” That’s where you get a referral fee, a small percentage of any purchase, whenever somebody follows a link from your own Web site to Amazon’s and then buys something. Lots of online stores offer similar programs. Well, when one of your Pinterest photos links to a product for sale online, Pinterest quietly modifies the link to insert its own affiliate code, so that Pinterest gets the referral fee. The revelation did raise some eyebrows, but you can change the link back, if you want.)

Second, Pinterest is unlike Twitter, Facebook and their ilk because you’re not just broadcasting, or even principally broadcasting. You create Pinterest boards for your own use, your own memory-jogging, your own inspiration. If other people find joy or use from what you’ve put together, great — but you can get tremendous mileage from Pinterest even without a following, which you can’t say about other social sites.

Finally, Pinterest gives you a break from the usual goal of social sites: self-absorption, self-documenting and self-promotion. As a Huffington Post post put it recently, Facebook and Twitter posts tend to “come with the silent subtext, ‘Here’s how great I am.’ On Pinterest, the tone seems to be ‘Wouldn’t this be great?’ ”