TCP-Flags??
 

I was reading some IPTables tutorial the other day, when I came across something like this that confused me:

iptables -p --tcp-flags SYN,ACK,FIN

My question is do what the following do:

SYN
ACK
FIN
RST
URG
PSH

:newbie:

The meaning of the flags or "control bits" is here, how they are used in everyone's favourite example, the "three-way handshake" here, and if you want an RFC description look here in Pt 3, 3.4 and 3.9 .

HTH somehow.