If you are creating a web-based form where you want the visitor to enter data and submit the form to the web server for processing, you may want to use SSL (secure socket layer) encryption service.This is especially true if you are entering credit card numbers or other sensitive information. 

When using SSL service, as the data is transmitted from the client's browser to the web server, all information on the form is encrypted. Once it is received at the web server it is automatically decrypted, and you can then store it or process it as usual on the web server