small doubt reg uname command

Am new to solaris can anyone explain the fields in the below command. Also let me know the difference between nodename and hostname. Here osnask2 is the hostname and type SUNOS. What abt the remaining fields.?

#uname -a
SunOS osnska2 5.8 Generic_117350-47 sun4u sparc SUNW,Sun-Fire-480R

have you tried google before asking? first hit for "solaris uname":

SunOS (Solaris) tips