which one is better wget or scp to copy files from one server to other?

I would prefer wget since it's much faster than scp. I've always experienced wget 5 times faster than scp.

Say, I have a gigabyte network. If I try to copy a large file through scp, the max rate may be 10MB/s while it can be as fast as 50MB/s with wget.

The problem is wget can only be used through http. But it's easy if you try with SimpleHTTPServer from python.

Use scp. wget is only useful to retrieve files using HTTP or FTP.