As what I know, an open TCP scan is just a normal TCP 3-way handshake followed by RST. It is detectable because the target will log this connection.

For the half-open TCP scan, it is defined as "stealth". The explanation is that **only a SYN packet** is sent, which is also a 3-way handshake.

But these two seems same. I do not find what are the true difference?