There are two major server side redirections are present , 301 redirection and 302 redirection. Redirections are useful for some situations like when we purchase a new domain name for our website and want to shift the entire website to new domain from old domain name. The shift is some how painful if the old domain is old and has a decent site rank. As we are not going to use the old domain name , we need to start everything from scratch. Another problem is the traffic which coming to the old domain. Those visits will get 404 error message where the requested page not found.
Reasons for using domain redirections
As described above the major reasons for using 301 and 302 server redirections are:
1. Retain the Page rank of the Old domain
2. Redirect the traffic to new domain from old domain
3. Prevent the lose of age domain and other site rank factors
Even though both are using to redirect one domain name to another a big difference in its working. Redirection 301 is using for permanent redirection where 302 redirection is for temporary redirection. If we are planning for a permanent migration to new domain from old domain we should use 301 redirection.

