Reread Hamlet's "speech on drama" to the three "Players" t the opening of Act III, Scene 2. Relying on what he says when he speaks the second time (beginning with "Be not too tame..."), tell in your own words what Hamlet, and ultimately Shakespeare, gives as the purpose of drama (or "playing" as Hamlet calls it).
Be not too tame neither, but let your own discretion be your tutor: suit the action to the word, the word to the action; with this special o'erstep not the modesty of nature: for any thing so overdone is from the purpose of playing, whose end, both at the first and now, was and is, to hold, as "twere, the mirror up to nature; to show virtue her own feature, scorn her own image, and the very age and body of the time his form and pressure. Not this overdone, or come tardy off, though it make the unskilful laugh, cannot but make the judicious grieve; the censure of the which one must in your allowance o'erweigh a whole theatre of others.