sp_password is a system stored procedure which is used to change the password.
syntax for sp_password is :
Example:
sp_password 'MY_OLD_PWD','MY_NEW_PWD'
syntax for sp_password is :
sp_password <old password > , <New Password >
(or)
sp_password @old = <old password >, @new = <New Password>
Example:
sp_password 'MY_OLD_PWD','MY_NEW_PWD'