May 13, 1991: Apple releases Mac OS 7, more commonly known as System 7.

The longest-lasting of Apple’s classic Mac operating systems, it will remain current until System 8 replaces it in 1997.

System 7 brought the biggest Mac OS shakeup since the operating system first shipped with the original Mac in 1984. The new version was whip-fast, beautiful to look at, and boasted a bevy of innovative features.

System 7’s new features

One big new feature was true full-time multitasking, letting multiple applications run at the same time. This meant that, for the first time, you could carry out background processing. It allowed Mac users to perform a processing-heavy task in one app while using another. That may sound (and is!) normal today, but it was a revolution in 1991.

In addition, users now had access to “aliases,” an idea later copied by Microsoft Windows 95 as desktop “shortcuts.” This made it easier to access individual files without having to track down the source application.

The new Mac OS also brought a big improvement in terms of file sharing. If you had an AppleTalk network, System 7 made it easy to share files and folders between systems with a simple peer-to-peer LAN.

It was even possible to collaborate on projects with a “Publish” and “Subscribe” feature. This meant that changes made to a file on one person’s machine automatically transferred to every other linked document. Think Google Docs is impressive? Mac OS 7 was doing something similar a quarter-century earlier!

A big improvement for Mac OS

Visually, the OS proved leaps and bounds better than its predecessor. TrueType fonts no longer suffered from their previously jagged appearance. System 7 also made the Mac desktop more customizable. The OS supported various color options, with a more streamlined appearance overall. (A new “Balloon Help” feature came to the aid of Mac newbies.)

Although it shipped with few packaged programs, System 7 quickly ushered in a range of multimedia applications. Later in 1991, QuickTime landed on the Mac, letting users run and manipulate video on their computers.

System 7 came preinstalled on new Macs. For upgrading users, a Personal Upgrade Kit cost $99 and came with 90 days of free technical support. A group upgrade for networks ran $349.

The operating system continued until 1997, when Steve Jobs arrived back at Apple. The last System 7 update came with April 1997’s Mac OS 7.6.1. Apple then replaced it with System 8.

Relive the glory with this System 7 emulator

Feeling nostalgic? Check out this System 7 emulator that runs inside your browser window.

What are your memories of using System 7? Were you a Mac fan at the time? Let us know in the comments below.