If you are the only owner of any website or blog and want to protect your admin directory then you can allow that admin directory for just your IP and deny from all others. Here it is how.
# just allow my computer and my IP to access admin of this site order deny,allow deny from all allow from xxx.xx.x.xxx
Where xxxxx digits will contain your IP address. This example will work if you use a static IP. You can check your IP from here.