Skills are the specific, recognizable part of an actor's work made evident in performance. Before there are skills, there is process. Process is the way in which an actor goes about discovering what it is performance skills should be applied to. There is no one process and, indeed, finding the right process for the right circumstance is itself a skill. Most actors work eclectically, using whatever elements of process seem to have worked for them over the years. But probably the most fundamental and commonly acknowledged, if not agreed upon, basic process is that of Stanislavski.
Leaving aside the controversial concept of emotion memory, already discussed, there are some basic principles of the Stanislavski system which are generally accepted, if not universally adopted, as a valid process for the actor's work on, at least, realistic texts. The process requires actors to approach a text by breaking it down into units of action, or 'beats'. There is a probably apocryphal story that it was originally little 'bits', but the Russian accent made it sound like 'beats' to the western ear! So beats we have; which does in fact lend an appropriately active and rhythmical sound to the process. Beats are units of textual time which have a consistent preoccupation with a specific action on the part of the characters: a period of time when characters don't change their objectives or tactics. The individual units fit consistently together to create the main action of the play.
We have just mentioned the character's objective. This is another part of the system. It is what the characters want, what their actions are geared to achieve, what they step on stage to get. The objective is complemented by the concept of the obstacle (whatever stands in the way of the characters getting what they