The non-bold, non-italic exercises can (apparently) be considered as basic or
auxiliary depending upon what other exercises they're programmed with. See these links:http://www.exrx.net/Questions/MuscularAnalysis.html
("Weight Training Exercise Utility Classification")http://www.exrx.net/WeightTraining/Glos ... hor1270300
Edit: Might as well just paste it here.
The classifications can be seen as a continuum. An exercise utility is also dependant upon the inclusion of other exercises. For example, an incline bench press is an auxiliary exercise in the context of a full body routine but a basic exercise in a split program. A step up is an auxiliary exercise when included with squats, but an auxiliary exercise if a leg extension is performed instead. You will find the definitions in the glossary eludes to relative characteristics.