any user is ftp user.

Adding the user to the ftp group will allow to use FTP, for 
security reasons anonymous users must be disable

firstly create the user.
useradd surendra
passwd surendra

then opne the FTP file:-
vi /etc/vsftpd/vsftpd.conf
add this line at the end of the file
userlist_deny=NO

then open this file,
vi /etc/vsftpd/user_list

and add the above created user in this file to access FTP
services.

and restart the FTP services
/etc/init.d/vsftpd start
chkconfig vsftpd on  ( for permanent on )

When create the user by default it is ftp user and he can
login in ftp.