Some info about .img files

[Guest cTn]

Hi guys, i am just trying to figure out how things works, etc

I would like to know, how exactly are recovery/boot .img setup ? why i am trying to figure out is, when i have latest Amon RAs recovery image on my Hero, can some things get messed up that are inside recovery.img when i am switching between multiple roms etc?

What i am trying to find out does android uses something like partitions on ROM ? (boot/recovery/system) which are "protected" ? (cant read whats on boot/recovery partition even when phone is rooted etc)

I think there is some nice wiki document about this somewhere, so if someone could throw me a link, ill be really thankful