It is well known that computer have a life expectancy. When I refer to the life expectancy of a computer I’m not referring to how long it will work, I’m referring to how long you can keep it up to date with supported software and get it serviced. Many machines will work for years past their life expectancy. If you are reading this on the model pictured on the right, your machine is definitely past its normal life expectancy.
There are two terms that Apple uses for machine that they no longer have hardware support: Vintage and Obsolete. Apple usually classifies a machine as vintage once it reaches 5 to 7 years past its initial release and obsolete models are those that are 7 or more years old. Apple doesn’t provide hardware support for vintage and obsolete models, however most models that are vintage can support the latest software and receive updates.
Once a machine becomes obsolete, however, it usually will no longer will be able to support the newest OS X and security updates. Once a machine has unsupported software the machine starts to be become more susceptible to security breaches. A common security breach comes from exploiting older software that has a known issue. Once your computer can’t accept a supported OS X (which is currently 10.10 Yosemite and 10.11 El Capitan) it reaches the end of its life expectancy because the machine is no longer is repairable by Apple and the machine cannot receive software updates.