When to use method="get"?
When using method="get" in HTML forms, all variable names and values are displayed in the URL.
Note: This method should not be used when sending passwords or other sensitive information!
However, because the variables are displayed in the URL, it is possible to bookmark the page. This can be useful in some cases.
Note: The get method is not suitable for large variable values; the value cannot exceed 100 characters.
<form action="test.php" method="post">
When using post you can get the value on other pages with $_POST;
<form action="test.php" method="get">
when using get you can get the value on other pages with $_GET;
for this method you can see the variable result on query string.
If you want to retreive the value whatever it is (USING post or get), you can get the value on other pages with $_REQUEST
All are send/recieve values from one page to another page.