It'a code conversion to prevent third party accessing

the process is like this 

client->request->enctypted->through cipher text->descripted-
>server

this is the process 

(it is used to secutity purpose)

I think this is the .....
is this correct

Encryption & decryption are terms From CRYPTOLOGY. In 
hardcore testing it is used for security testing. 
Encryption is the process of transforming information using 
an algorithm to make it unreadable to anyone except those 
possessing special knowledge.
Decryption is the reverse process to make the encrypted 
information readable again.
It is used in applications using scecurity process for the 
system.Widely used for passcode testing & accounts testing 
for credit cards & banking softwares.

Hi ajay 
         This  is sunithaYagnamurthy.......
 Encryption:Converting the data into not understandable 
data (means binary codes etc) i.e,called Encryption
Decryption: Converting the data into Understandable format 
i.e called Decryption

If any mistakes is thr please excuse

sory sunitha i think ur answer is not correct & clear ..
frnds can any body give me the correct answer......?

I agree with Jimut.Encryption is a process of making your 
data not understandable to anyone and vice versa decryption 
is the process of again making the data in understndable 
format.

Encryption is the conversion of data into a form, called a 
cipher, that cannot be understood by unauthorized people. 
Decryption is the process of converting encrypted data back 
into its original form, so it can be understood. Encryption 
and decryption should not be confused with encoding and 
decoding, in which data is converted from one form to 
another but is not deliberately altered so as to conceal 
its content.