Copying files should be simple, yet there are a number of ways of transferring files.
Some of the ways that I could think of are listed here.

# -a=archive mode; equals -rlptgoD
# -r=recurse into directories
# -l=copy symlinks as symlinks
# -p=preserve permissions
# -t=preserve modification times
# -g=preserve group
# -o=preserve owner (super-user only)
# -D=preserve device files (super-user only) and special files
# -v=verbose
# -P=keep partially transferred files and show progress
# -H=preserve hardlinks
# -A=preserve ACLs
# -X=preserve selinux and other extended attributes
$ rsync -avPHAX /source /destination

# cross systems using ssh
# -z=compress
# -e=specify remote shell to use
$ rsync -azv -e ssh /source user@destinationhost:/destination-dir

# -xdev=Don’t  descend  directories on other filesystems
# -print=print the filenames found
# -p=Run in copy-pass mode
# -d=make directories
# -m=preserve-modification-time
# -v=verbose
$ find /source -xdev -path | cpio -pdmv /destination

# let's not forget good old cp
# -r=recursive
# -p=preserve mode,ownership,timestamps
# -v=verbose
$ cp -rpv --sparse=always /source /destination

# tar
# -c=create a new archive
# -v=verbose
# -f=use archive file
$ tar cvf - /source | (cd /destination && tar xvf -)

# scp
$ scp -r /source user@destinationhost:/destination-dir

# copy an entire partition
$ dd if=/dev/source-partition of=/dev/destination-partition bs=<block-size>