What is Exchange Server?

1.It is an Application from Microsoft to provide Email communication.
2.It works in Client/Server Model. 
3.It is used not only for emails, but also used for document sharing, voice and mobile communications.(we need use another tools to provide voice support)

    Exchange server = Email server

Note:Exchange server doesn't store any usernames and passwords its stores only emails

The email servers are two types

1.Public email server

2.Private email

Disadvantages of Public Email Server (form Exchange administration point of)

1. No Identification of Email Address: We don't get with our Domain Name.

2. There Is No Complete Data Security: If we get delete the data we need contact our administrators. It's difficult in public servers.

3. Internet Requires 24/7 Without Downtime: Without internet we can't use. In Exchange server Communication is possible without internet.

4. Monitoring of Email Account Is Difficult: Monitoring public emails is difficult in real time. What Employees are sending.