One of the biggest improvements Apple made with its Mac OS 10.10.3 update that rolled out to users last week is the introduction of the NVMExpress protocol, which promises faster SSD performance on the latest Macs, including the all-new 12-inch MacBook.

While the new Photos app and a ton of new emojis stole the spotlight when the OS X 10.10.3 update dropped, Apple made some significant improvements to Yosemite under the hood, and the addition of NVMe is the biggest one that went unnoticed.

NVMe can deliver significantly faster performance from PCIe-based SSDs, like those built into the new MacBook and latest MacBook Airs, and those that can be added as an optional upgrade to the MacBook Pro, iMac, and Mac Pro.

Until now, Apple has been using the AHCI (Advanced Host Controller Interface) protocol, which "dates back to 2004 and was designed with hard drives in mind," explains Anandtech.

"As a result AHCI can't take full advantage of SSDs and since the future is in non-volatile storage (like NAND and MRAM), the industry had to develop a software interface that abolishes the limits of AHCI."

That new software interface is NVMe, which is short for Non-Volatile Memory Express, and was developed by a consortium of industry giants, which included Intel. In addition to reducing latency by 50%, NVMe is faster than AHCI, and is more power efficient.

The easiest way to see if your Mac has a NVMe compatible drive is to open up the System Report by clicking the Apple icon, selecting "About This Mac," and then clicking the "System Report…" button (after upgrading to OS X 10.10.3).

An "NVMExpress" string will be listed under "Hardware," and if you click this, any supported drives will appear. If your Mac does not have a PCIe-based SSD, System Report will tell you it "doesn't contain any NVMExpress devices."