When starting up an old Mac running the Classic Mac OS, you would see a number of installed system extensions loading along the bottom of the screen, but when you start up OS X, you are shown a fairly bland image of a gray background with an Apple symbol that appears. During this time, a number of background processes are starting up to allow you to use your system; however, you are not shown these and instead are shown either a progress bar or spinning wheel of sorts that simply indicates to you that something is happening, but does not say what. Continue reading ⇒