When you register for an email address, you are often registering for a variety of other services as well.  All of the major email providers now offer additional services that email users can access.  Google offers access to most of their services with the creation of a Google Mail account, including Drive, Calendar, Google+, YouTube, and more, Microsoft accounts allow you to access Outlook, SkyDrive, Office 365 (with subscription), and create an Xbox gamertag. iCloud mail comes free with an Apple ID, and allows you to send and receive emails using aliases to protect your email address. Yahoo! accounts allow you to create a custom homepage, which you can link with your Facebook account. Most free email accounts come with a limited amount of storage space. While the free amount is typically more than enough for the average personal use, business users may find that the storage is insufficient for high-volumes of emails. Most free email services can be upgraded with more storage for monthly payments. The extra storage will apply to all related services. For example, buying extra storage for Gmail will increase your Drive storage as well. Most internet service providers offer multiple email accounts with your internet package. These can often be accessed through the provider’s home page. Using one of these accounts may be more appealing than setting up a new one, as you are already paying for it with your internet subscription. If you feel like you might change service providers frequently, avoid using their email addresses for anything important You may lose easy access if you change service providers. When you register with a web hosting service, you often receive email accounts that include your domain name. This is especially useful for small business owners, as it allows your email to seem more professional, as opposed to sending email from a free service.

TL;DR in Chinese:
对比一下每个账号所能提供的服务。 确定你需要的电子邮件类型。 查看一下你的互联网运营商。 创建一个网站。