What does savvy mean in the book The Outsiders?

In the novel The Outsiders by S.E. Hinton, the term "savvy" is frequently used as an expression of understanding or acknowledgement. It is commonly employed as an informal confirmation or agreement between the characters. For instance, when Ponyboy reveals his thoughts about the Socs, Johnny responds with "yeah, I savvy," indicating that he comprehends Ponyboy's sentiments. "Savvy" is a colloquial expression that underscores the closeness and camaraderie among the main characters. It adds to the authentic portrayal of teenage language and camaraderie within the novel.