Ramp InfoTech Groups

1.  List content type and site content type means?
2. I created one custom Webpart. Now my custom Webpart should display whenever I create a new site.
3. Difference between solutions and features?
4. What kind of permission levels need to run the stsadm cmd tool?
5. How to deploy only .doc files to document library by using event receivers?
6. Alternative mapping means?
7. How can you upload collection of documents by using SharePoint object model?
8. I created one custom Webpart? Now I want deploy it to specific sub site. How can do it?

          Will post the answers to the above Questions soon.