[citation][nom]JOSHSKORN[/nom]Go take a class in computing and stop using Google.[/citation]
I guess you haven't done either. Yes, 1byte=8bits but there is something called 'overhead' in almost every kind of data transmission. That means that out of the 1Gbps 'moving' in the cable some are user data and some are protocol data. When you observe a copy progress, that only reports the user data. Ethernet protocol effective throughput is approximately 70%. Therefore a 90MB/s user data transfer is around 0.7Gbps (as user Regnar-Kon mentioned above) which is maxing out the effective throughput of a 1Gbps connection.