Describe the other Greaser gangs. What are they each like?

When the gang gets to the vacant lot, Tim Shepard and his gang are already there. Ponyboy notes that the difference between their gang and the Shepard gang is that Tim Shepard uses "strict discipline;" there is a clear leader and they are organized, while Ponyboy's gang is "just buddies who stuck together." There's also another Greaser gang from Brumly, a suburb. Ponyboy thinks the other gang members really look like "hoods".