Mac OS X Yosemite promises to be a big update for Apple's desktop -- and you can get an advanced beta copy for free starting Thursday, July 24.

With the public beta release of OS X Yosemite (10.10), Apple is doing something it hasn't done in 14 years, when the very first OS X (10.0) operating system was released: it's offering a pre-release for anyone in the public willing to try it out and give Apple feedback. Here are the top features to expect in Yosemite public beta and how to download a free copy for your own hands-on preview.

Public Beta: Atypical for Apple, Unprecedentedly Free

Back in 2000 when Apple made the risky, revolutionary shift from OS 9 to OS X (and when many of our readers were still in grade school), it first released a public beta of the brand new operating system to flatten out as many kinks as it could before the official release. At the time, the OS X public beta cost $30 and came in the "mail" on a "CD-ROM."

Obviously a lot has changed since then, including the fact that technology companies -- especially Apple -- now hate operating system fragmentation (i.e, customers using various, sometimes outdated, versions of system software) and value having their customers' devices working in digital lockstep more than making a buck from a new OS. It's now standard practice to allow customers to upgrade to a new Android, iOS, OS X, or Windows operating system for free. But Apple is going a step further than it has before by allowing a select number of "regular" people -- not just software developers -- to preview the pre-release version of OS X Yosemite.

How to Get OS X Yosemite Public Beta for Free (with Caveats)

Apple announced the open public beta for Yosemite at WWDC 2014 earlier this summer, and has opened a webpage where you can sign up to get early (and free) access to the new operating system.

Getting on the list is as easy as signing in with your Apple ID and password. When the beta software is ready for you, you'll get an email with a code and a link to download and install Yosemite from the Mac App store. That should be soon, as OS X Yosemite Beta is being released around 10am Pacific Time on Thursday, July 24.

But there are some caveats to be mindful of.

First, Apple is only releasing Yosemite Beta to the first million users to sign up. We were able to sign up this week, but there's no telling if the one million mark has already been reached, except if Apple takes down the signup link, so if you're interested in testing Yosemite, sign up now!

Second, you'll have to have OS X Mavericks to upgrade to Yosemite Beta. That shouldn't be a big problem if you're interested in testing out the new OS X because it's likely you already run the most up-to-date Apple software, but if you haven't installed Mavericks, you'll have to go to the Apple Store and download it (also for free) first. As far as system requirements go, if your machine can run Mavericks, it's capable of running Yosemite. Here's a list of Yosemite-compatible Macs.

Third -- and this is probably the most important warning for everyday Apple enthusiasts interested in testing Yosemite Beta -- you'll want to be very careful about where you're installing Yosemite Beta (or for that matter, any beta software).

All betas, including open public beta programs, are likely to contain errors, incompatibilities, or features that just don't work. In fact, getting a million people to find and report these problems for free is the entire reason behind the public beta release. Speaking of which, when you install Yosemite Beta, you have to agree monitoring software that automatically reports bugs, crashes, and usage data back to Apple, though that can be disabled later in system preferences.

Because of the risks involved with testing unfinished software, Apple itself suggests using a secondary Mac to try out Yosemite on -- putting a beta OS on any machine you rely upon for you're your daily life or (especially) work is a risky move. If you don't have an extra guinea pig Mac on hand, at least make an isolated partition on your storage drive to install Yosemite Beta, and always back up your files.

It Takes Two, Baby: Why The Coolest Yosemite Feature Won't Be In Beta

The final caveat regards the kinds of features you'll get to experience in Yosemite Beta -- and the most anticipated features of Apple's new OS X that you won't.

With Yosemite Beta, the you will get to see the most obvious change, which is to the look of OS X. So you'll get to see the new iOS 7-inspired flat interface, along with changes in system font and a more pronounced type of UI translucency that should make everything look crisper and cleaner on Retina displays. And if you frequently use your Mac in dark meeting rooms or lecture halls, you might want to test the new "Dark Mode" in Yosemite.

(Photo : Apple)

Other enhancements, which we covered during the WWDC 2014 announcement, include a new version of both the Notifications Center and Spotlight search that may make those features actually useful. Notifications Center will include a "Today" view borrowed from iOS that gives you a quick look at your calendar, stocks, weather, and other widgets. Spotlight has been enhanced to search for anything, including instant-launch apps, on the web, Wikipedia previews, contact information, and of course local files.

But the coolest new features in Yosemite won't work in the open public beta version, because they involve Apple melding OS X with iOS devices in much more comprehensive ways.

(Photo : Apple)

In order to test those features, such as Handoff, Instant Hotspot, iCloud sharing, SMS through Mac Messages, caller ID, routing phone calls to your Mac -- basically any of the most exciting "Continuity" features coming this Fall with the official iOS 8 and OS X Yosemite releases -- you'd need an iPhone running iOS 8, which is not available in a free public beta.

So should you get Yosemite Beta? Yes, if you're a diehard Mac fan that's happy to deal with bugs and can protect your data. But if you're ansty to get your iPhone and Mac to work together better than ever before, just wait for the Fall.

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