Get and Post are among many methods defined under http protocol.
Get method is used to get specific resource. Data sent through get method is visible in URL query
string. All data reside in http header. This method is generally repeatable (idempotent) meaning sending it multiple times doesn't harm. For example clicking
http://www.yahoo.com twice.
Post method is generally used to submit form data and get required response. Post method data are part of the message body (payload) and not header. Data sent are not visible in URL and the method is non-idempotent. Sending post requests multiple times can cause undesirable results. For example, submitting purchase button twice!
Usually, we override doGet and / or doPost methods defined in HttpServlet to provide required response to client's get and post requests respectively.
[ July 02, 2008: Message edited by: Siddharth Naik ]