Difference between QTP, Selenium and Silk test

Difference between QTP, Selenium and Silk test
 
.QTP
QTP can be used for testing client server applications
QTP is limited to Internet Explorer on Windows.
QTP uses scripting language implemented on top of VB Script
 
 
Selenium
Only web applications can be tested using Selenium testing suite
Selenium supports following web browsers: Internet Explorer, Firefox, Safari, Opera or Konqueror on Windows, Mac OS X and Linux
Selenium test suite has the flexibility to use many languages like Java, .Net, Perl, PHP, Python, and Ruby.
Selenium 2.0
 
 
 
Boarland silk test
Silk Test can be used for testing client server applications
Silk Test is limited to Internet Explorer and firefox
SilkTest Classic uses the domain specific 4Test language for automation scripting. It is an object oriented language similar to C++