Apple's macOS Catalina (10.15) will make its official debut later in the year, although there will be a publicly-available beta version next month. 

macOS Catalina is the next version of macOS, the operating system that powers Apple Mac computers. 

The macOS 10.15 system requirements are very similar to last year's for macOS Mojave - that OS brought a bit of a cull for support for some older Macs - it supported Apple computers made from 2012 onwards. Catalina again supports Macs made from 2012 onwards. 

The predecessor, macOS High Sierra, ran on many older machines even back to 2009.

macOS 10.15 Catalina supported Macs

  • MacBook (2015 or newer)
  • MacBook Air (2012 or newer)
  • MacBook Pro (2012 or newer)
  • Mac mini (2012 or newer)
  • iMac (2012 or newer)
  • iMac Pro (from 2017)
  • Mac Pro (2013 or newer)

The only difference between the system requirements for last year's Mojave and this year's Catalina is that some older versions of the Mac Pro - from 2010 and 2012 -are no longer supported.  

Of course, Apple can't support its hardware forever. Some new features need better processors to work and the older a machine is, the less powerful it tends to be.