What version of Mac OS X is pre-installed on the "Unibody" MacBook Pro models?

All "Unibody" MacBook Pro models prior to the "Mid-2010" line shipped with a version of Mac OS X 10.5 "Leopard," the discontinued "Mid-2010" and "Early 2011" MacBook Pro lines shipped with a version of MacOS X 10.6 "Snow Leopard," and the current "Late 2011" MacBook Pro line ship with a version of MacOS X 10.7 "Lion."

For specific build numbers shipped with a particular MacBook Pro, please refer to the applicable specs page for the model of interest.

For the maximum supported version of Mac OS X for all "recent" -- G3 and later -- Macs, please refer to the Maximum Supported Mac OS listing.

Can the "Unibody" MacBook Pro run Mac OS 9/Classic applications?

No. Apple provides no support for running Mac OS 9 or the "Classic Environment" on Intel-based Macs like the "Unibody" MacBook Pro. Intel-based Macs rely on the "Rosetta Universal Binary Translator" to run software for Mac OS X for PowerPC, and this emulator cannot run "Classic/Mac OS 9" applications.

Additionally, the "Unibody" MacBook Pro models ship, or shipped, with Mac OS X 10.5 "Leopard" or Mac OS X 10.6 "Snow Leopard", which additionally provides no support for "Mac OS 9/Classic" applications.

If you have a mission critical application that only runs on Mac OS 9, you likely would be best served by maintaining a PowerPC-based Mac. However, you may also be interested in reading "Are there any third-party programs to run Mac OS 9/Classic applications on Intel Macs?" from the Mac OS 9/Classic Support Q&A.

Site sponsor Operator Headgap Systems specializes in refurbished, and often heavily upgraded, systems capable of booting in both Mac OS X and Mac OS 9. Site sponsor PowerMax also sells systems capable of running Mac OS 9/Classic.

Can the "Unibody" MacBook Pro run Windows?

Yes. For those unfortunate ones condemned to use Windows, the Windows on Mac Q&A provides answers for just about everything you need to know about running Windows on the "Unibody" MacBook Pro or any other Intel-based Mac.

Can the "Unibody" MacBook Pro run Linux?

Yes. All Intel-based Macs are capable of running a number of Intel-based distributions of Linux through Apple Boot Camp or by using "virtualization".

For more on Boot Camp and Virtualization, please refer to the Windows on Mac Q&A.