1tb Western digital black hard drive much faster than a green?

Will a 1tb WD black hard drive be a lot faster than a 500gbh WD caviar green? Just interested because i have spotted a WD black 1tb for a good price and did want to get an SSD but might save the money and make do with that if it would be a noticeable improvement over my green.

It will be noticeably quicker, yes, although not dramatically. It might be higher density platters, hard to know because it's dependent on how old the Caviar Green drive is, but the main difference will be the platter speed.

It won't, of course, be anywhere near to the difference between a mechanical drive and an SSD.