Three Way Handshake - Transport Layor

I'm trying to understand how the Transport Layer uses the 'Three Way Handshake', I understand the general concept is as follows:

• user sends connection request
• server sends acceptance
• user sends data
• user sends disconnect request
• server sends acceptance

But I don't understand how the errors occur, I've been studying a few diagrams but they just confuse me, does anyone have any simple diagrams to shows this process?

I apologise if this is in the wrong section but it's kind of in-between programming and networking yet the only networking section is for server side and that's not related to this.

Thanks

 

http://www.inetdaemon.com/tutorials/internet/tcp/3-way_handshake.shtml

Host A sends a TCP SYNchronize packet to Host B
Host B receives A's SYN
Host B sends a SYNchronize-ACKnowledgement
Host A receives B's SYN-ACK
Host A sends ACKnowledge
Host B receives ACK. TCP connection is ESTABLISHED.

This means that A sends a request to B, B receives it, and sends a request back to A, then A sends another request back to B, three acknoledgements, three verifications for a connection.