Why we use email? Kindly chek out for any mistakes plz

It's a very easy way to communicate with family, friends and others
think about it,if you want to send a message to someone via mail,then you have to wait utleast 3-week until they get your leter,with E-mail they can have your e-mail with only one click. Without a email you would not be able to go onto facebook or hotmail or a lot of things.

When we sent an email, we use the address field to rank people as primary and secondary recipients. Primary recipients are those whose addresses are shown in the ‘To' field. They are the people for whom (ideally) we think the email's contents have most relevance.
Secondary recipients are those in the ‘Cc' field and for whom (ideally) we consider the email has less relevance. In practice, we receive large numbers of emails every day whose relevance to us is very obscure.
The most important function of copying people into an email is to provide information and keep them oriented about the progress of a project. Copying in on emails is an efficient way of sharing information. The copied in email can also serve as documentation that something has been done.
Copying in on an email can be used indirectly to invite others to participate. Being copied in does not necessarily require an answer, but it permits the recipient to do so if they wish. A copied in email can also be used to request feedback, whether for support for an issue or praise for a task that has been done.
Copying in on an email can also be used strategically to build networks and alliances.