We can verify the server side images.

Sorry yoganand u r wrong. here is the answer.

Accessibility check point identifies areas or ur web site 
that may not conform to the W3C web content accessibility 
guidelines.

when u develop a web application it is necessary to fallow 
the W3C guidelines. the Accesbility Check Point is used to 
find wether the web application fallow the W3C guidelines 
or not.

Anwser #2
Anwser #3
 are correct
w3c==www consortium standards
of web applications

Accessibility chk point used for a/c 508 compliancy to be 
checked. www consortium standards
of web applications is checking

Accessibility check point is to check the alternative
properties of a image or image link for web application. It
is a hidden checkpoint.

Accessibility check point is used for checking the world 
wide web consortium standers in order to confirm wether the 
page can be accessed all over the world.

Hi  correct me if am wrong 
Accessibility chekpoints are used to check the ALT
properties of the application under test(AUT). Like checking
how the tab button of keyboard moves the selectin of the
objects in a serial order as how it is structured.

Any web application should follow the w3 consortium standard
guidelines, so the AUT can be checked by using this
accessibility checkpoint.