Apple Developer Connection (ADC) has published an article titled
“Developing 64-Bit Applications” on its Web site. The piece explains the switch from 32- to 64-bit computing that will come with the release of Mac OS X v10.4 “Tiger” next year, enabling developers to go beyond the 4GB limitation on RAM currently imposed by Mac OS X on each application. Tiger ups the ante to 16 exabytes, or 16 billion gigabytes — enough to hold 16,000 copies of the Internet Archive, which is dedicated to maintaining an archive of the Internet. While no computer can hold that much memory, Apple notes: “There’s a lot of headroom for the future and it will take a long time to exhaust the potential of the 64-bit address space.” You can read more on the ADC site.