Difference between "Date" and "Received" fields in the message list box

Hi, What is the difference between the "Date" and "Received" fields in the message list box? I would have assumed that the Date field is for the date and time the message was sent by the sender. And the Received field is for the date and time the message arrived in my inbox '''in Thunderbird'''. What I seem to be seeing is that the Received field is indicating the same date and time as the Date field or, in some case, a time that is one or two minutes later. Does the Received field indicate when the message arrived at the inbox '''on my POP server''' (hence the occasional delay of a couple of minutes)? Is there a way I can have a column to display the date and time when I downloaded the message to my Thunderbird inbox? Thanks.