The dialect ranges from a 'standard' Swabian, spoken in Stuttgart, to slightly differing and 'thicker' forms found in smaller towns in the countryside.
True Swabian, with its nasal intonations and grammatical adjustments to common words (German 'haus' becomes Swabian 'haeusle'), is known for being difficult for speakers of Standard German to understand.
As well, Swabian contains vocabulary that differs altogether from Standard German (eg. 'jam' in Standard German is Marmelade while in Swabian it becomes G'saelz).