Query String is one of the caching technique used in asp.net to speed the process of response to repeated requests. It has the followings plus and minus.

Plus

1. It doesnt require any server side resources.

2. All the browsers supports.

Minus

1. The information is passed along with the url making it visible to all.

2. The browser import a constraint of specific size on this hence only

restricted size of data could be passed.

Query string is one the ways we can maintain the user session over http.

When we request for a page and want to pass some parameters to that page and the data required is not sensitive we can use Querystring. Also through query string we can send only limited number of characters.