Absolutely, my wife and I e-mail often, I'm on hotmail, she is on gmail.
You can write a mail to a person on hotmail. You can send the person mail from Gmail to hotmail easily. Gmail supports this kind of sending mails.
Gmail and Hotmail both are mail servers. They both can send and receive mails. The only difference being Gmail is more popular than hotmail.
Gmail users can easily email Hotmail users. Gmail allows their mails to send to other mail servers. Hotmail can also receive their corresponding Gmail mails.
User can send a mail from Gmail account to other ones. Hotmail and Yahoo are examples of those. Gmail provides cross server mailing too.
You can send mails from Gmail to other mails. Gmail allows sending to yahoo, hotmail etc. This increases the functionality and it's scope.
No, Gmail account can only be created via google ID. You cannot make it by Hotmail ID. However you can send mails between these two.
Gmail Yahoo and Hotmail are mail servers. They can be used to send and receive mails. Outlook uses these mail servers to sync at one place.
Gmail and Hotmail both are good for business. Gmail has more modules and better features. This can be the advantage of Gmail over hotmail.
Gmail and Hotmail are two different email services.
Hotmail came before gmail.
One of the major differences between gmail and hotmail are the size of file attachments you can send. Hotmail attachment size is limited to 10mb while gmail allows 20 mb. Hotmail also allow a full preview of your email before you open it.