Joe Balestrino discusses the value of subdomains.�ǰ���˹����ŵ���۵ļ�ֵ�������� The four key points are:�ĸ��ؼ���ǣ�

  1. Subdomains are treated as a domain as far as developing a new site is concerned.�ӱ���Ϊһ����ͷ�չһ���µ�վ���ǹ�ע��
  2. One way links from subdomains are valued as from a domain.����һ���������ӵ�������ļ�ֵ����Ϊ��һ����
  3. They rank as well as a regular domain.���ǵ�ְ�����Լ���Ϊһ�������Ե�����
  4. Banning of a subdomain may lead to banning of the main domain.��ֹ��������ܻᵼ�½�ֹ����Ҫ���� It has sometimes happened.����ʱ����

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I think the additional values of subdomains are:����Ϊ�����ֵ���������ǣ�

  1. They allow you to maintain brand identity.���ǿ������Ʒ������
  2. It is much easier to get a subdomain name of choice.���Ƿdz����׵õ������������Ƶ�ѡ��

In summary subdomains offer lower cost of developing new sites / web services for legitimate businesses.�ڼ��׳�����������ṩ�ɱ��ϵ͵ķ�չ�й�ҵ�����վ/ Web����Ϊ�Ϸ�����ҵ��