security testing: 
  The process to determine that an information system (IS) 
protects data and maintains functionality as intended.

Functional Testing:
  Testing if the required functionality is working as per 
the specifications and if the expected result is correct.

Security testing:
                 The security testing is performed to check 
whether there is any information leakage in the sense by 
encryting the application or using wide range of sofware's 
and hardware's and firewall etc.

Functionlity Testing:
                     To check the application that works as 
per the specifition's or not.It also called as blackbox 
testing.

Muralidharan
dharanmu@yahoo.com