This phrase highlights socioeconomic disparities and is often used to describe societal divisions.

Class Division

The 'tracks' refer to train tracks, which physically divided towns into richer and poorer areas in the past.

Idiomatic Geography

Used metaphorically, it's not about literal geography, but a commentary on class and origins.

This definition carries a moral connotation, implying disapproval of certain behaviors.

It doesn't necessarily mean involvement in illegal acts, but rather association with disrepute or dishonor.

Being from the wrong side can imply a character's mysterious or troubled past.