Differences among scp and rsync in Linux

Question

What is the differences among  scp and rsync in Linux?

Answer 1

scp- copying files by using ssh(secure copy) of the chosen files from the source host to destination host and while finished closes the scp application

rsync- you have to setup the key authentication among the servers that do the synchronization (to destination system to contain the source public key in destination host's authorized_keys) and copies the files through source to destination whenever there is a modification(addition/deletion) in the source directory  can be pull/push/both