Get psyched, Mac fans! It’s that time of year again, and a new, free upgrade to your operating system is on its way from Apple (AAPL).

Yes, Apple will unveil new machines this season, including the iMac Pro: the most powerful Mac ever made. Dark gray metal, 5K screen, an Intel Xeon chip with up to 18 cores, 128 GB RAM, 4 terabytes of solid-state storage, and a 10 GB Ethernet jack. $5,000 and up. A truly monster machine—and yet it’s not the long-awaited update to the Mac Pro; that’s coming, too, Apple says.

No, the Mac OS High Sierra is coming to all of us, even with older Macs. The name suggests exactly what it is: a set of refinements to the current Mac OS, called Sierra.

What you’ll soon discover is that (a) it’s a whole lot of miscellaneous, and (b) it’s a lot of stuff that’s also coming to iOS 11 on the iPhone next week.

Still, there’s a lot of useful stuff. Here’s what you can look forward to.

Safari

Apple has continued to work on Safari, its web browser—and says that the new version will be the fastest desktop web browser in the world.

It will also use less power. Apple claims that you’ll be able to watch Netflix (NFLX) for two hours longer in Safari than other browsers.

Maybe even more thrilling to the world’s internet surfers (and less thrilling to advertisers), Safari will be able to auto-block auto-play videos. Now, no video will begin playing unless you click it. (You can grant certain sites permission to autoplay every time, if you like.)

That’s not the only way Safari will frustrate advertisers. Apple says that “Safari now uses machine learning to identify advertisers and others who track your online behavior, and removes the cross?site tracking data they leave behind.”

This is cool, too: You can create different viewing settings for different sites. You might like the New York Times site to appear with larger text, ad blocking turned on for Dilbert.com, and so on. (Page zoom, location services, notifications, and ad blockers are among the settings memorized for each site.)

And if you like the Reader view—which hides all ads, navigation stuff, blinking stuff, competing colors and fonts—you can now tell Safari to use it for everything. Every time you open an article that works with Reader, it pops into that format automatically. You end up with far fewer migraines from just trying to surf the web.

Apple File System

The file system is the underlying software that organizes all your documents, photos, mail, and so on. The one driving the Mac is now 33 years old.

So the big-ticket item underneath Mac OS High Sierra is the Apple File System, developed for the new era of solid-state drives and increased security threats.

All of this is probably very satisfying to programmers. But you, the average person, will probably notice only a couple of changes: First, when you duplicate a file or folder, it happens instantly. There’s no progress bar, no wait. Second, getting the size of a folder is also instantaneous.

Photos

The Photos app has received a lot of work. Now, the left side has an ever-present sidebar, showing your photo groups. A new Imports view shows not just the latest batch of imported photos, but the batch before that, and the batch before that, and so on.

You can now filter your view by Favorites, photos you’ve edited, only movies, only stills, and so on. The Faces feature, which knows who’s in each photo, has been improved, and the face-categorizing you’ve done on the Mac gets auto-synced to your phone.

New editing tools bring Photos ever closer to Photoshop. You can now manipulate the Curves of a photo’s histogram, or edit only the reds (for example) in a photo. And, inevitably, there are now Instagram-style filters.

Better yet, you can now send a photo to Photoshop (or any other external program) for editing, just as you could in iPhoto. Better yet yet, the changes you make in that app are non-destructive—you can undo them at any time. In other words, you can use Photos for its superior organizational and sharing tools, but Photoshop for editing.

The Photos feature called Memories (automatically grouped and curated slideshows with music) are much smarter now. Instead of grouping photos only by event or location, they now auto-recognize and auto-build slideshows of your pets, babies, outdoor activities, performances, weddings, birthdays, and sports games.

Finally, Apple introduces some editing options to Live Photos: weird, three-second video clips that the iPhone can capture. In Mac OS High Sierra, you can shorten a Live Photo, mute its audio, or extract a single frame to use as a still photo. Photos can also suggest a “boomerang” segment (bounces back and forth) or a loop (repeats over and over). And it has a new Slow Shutter filter, which (for example) blurs a babbling brook or stars moving across the sky, as though taken with a long exposure.

Notes

The Notes app continues to develop:

• Pin your best Notes. In the Notes app, you can now pin your most used notes (to do lists, grocery lists, etc.) to the top of the list, so they don’t get sorted down chronologically as they do now.

• Tables. Yes! You can now add a table to a Note. Great for bake-sale assignments, sports scores, and so on.

Misc

• Smaller multimedia. Apple is adopting new file formats for photos (HEVC) and videos (H265), which look the same as they did before but consume only the half the space. (When you export to someone else, they convert to standard formats.)

• Mail enhancements. When you search in Mail, a Top Hits section presents the messages Mail thinks are the best matches (based on Read status, senders you’ve replied to, your VIPs, and so on). Mail also offers a split-screen view when composing new messages in full-screen mode. And it stores your messages in 35% less disk space. More space is always welcome.

• A new voice for Siri. The new male and female voices sound much more like actual people.

• iCloud file sharing. Finally, you can share files you’ve stored on your iCloud Drive with other people, just as you’ve been able to do with Dropbox for years.

• Capture a FaceTime moment as a Live Photo. You can snap a 3-second snippet of a video chat—a Live Photo—for later sharing. (You can’t do so secretly, however; the other person knows.)

• Messages in iCloud. When you sign into any new Mac, iPhone, or iPad with your iCloud credentials, your entire texting history gets downloaded automatically. (As it is now, on a new machine, you can’t see your chat histories.) Saving the Messages history online also saves disk space on your Mac.

• Family storage sharing. You can now share an iCloud storage plan with family members.

• More Spotlight wisdom. The Spotlight search feature can now provide flight arrival and departure times, terminals, gates, delays, and flight maps. It can also return multiple Wikipedia results on a single screen.

• Developer goodies. Apple now offers development kits for virtual reality and augmented reality, hoping to jump-start new apps in an area where Apple is now way behind. There’s a new version of Metal, too, the Mac software that addresses your graphics card.

Hi, High Sierra!

This is one of those off years, where Apple takes a breather (and gives us a breather). Instead of piling on new stuff to find and learn, it cleans up what it’s already got.

There’s nothing wrong with that. In fact, the world probably wouldn’t mind if more companies adopted that schedule.

Head over to Yahoo Finance on Tuesday to check out our coverage of Apple’s “special event,” during which it’s expected to unveil its 10th-anniversary iPhone.

More from David Pogue:

T-Mobile COO: Why we make investments like free Netflix that ‘seem crazy’

How Apple’s iPhone has improved since its 2007 debut

Gulliver’s Gate is a $40 million world of miniatures in Times Square

The 5 best new features of this week’s YouTube redesign

Samsung’s Bixby voice assistant is ambitious, powerful, and half-baked

Is through-the-air charging a hoax?

David Pogue, tech columnist for Yahoo Finance, is the author of “macOS Sierra: The Missing Manual.” He welcomes nontoxic comments in the comments section below. On the web, he’s davidpogue.com. On Twitter, he’s @pogue. On email, he’s [email protected]. You can read all his articles here, or you can sign up to get his columns by email.