.com- This is the general commercial site.
.net- This suffix usually is reserved for network/Internet service providers, but there is not set policy on this.
.org- This suffix is for service Organisations/Non-profit Organisations.
.edu- This suffix is for education institution sites. You must prove you status to register any .edu domain names.
.gov- This is only for use by government agencies. It's not likely that you qualify for this suffix.
