Because the Preview app built into Apple’s Mac OS X often surfaces only when Mac users double-click a photo or PDF file — and because of its name alone — it’s easy to think this program exists solely to help you view images. But over the last few updates to OS X, Apple has turned Preview into a capable editing tool for many basic jobs. As a look around its Tools menu will show, it easily handles the standard image chores of cropping a photo or resizing an image. Preview can do those same tricks with Portable Document Format files and also lets you annotate them with text, highlighting and lines and shapes. You can even even combine separate PDFs into a single, multiple-page document by dragging them on top of each other in Preview’s sidebar. This program won’t put a “real” image editor out of business--but like the upgraded version of Microsoft’s Paint application in Windows 7, it does more than it gets credit for.

(About the “PostPoints tip” title: I archive each tip-of-the-week e-mail we send to PostPoints members under this blog’s “Tips” category. Today’s item went out on March 8.)

In other news...

*Sunday’s column compared the two most widely-used tax-prep applications, Intuit’s TurboTax and H&R Block’s Block At Home--and suggested two ways to cut down on the need for this entire category of software.

* I also wrote an extra column Saturday, relating my first impressions of the iPad 2.

* And in Help File, I addressed a question that once might have seemed unimaginable: Are we really getting less spam in our e-mail?