We've been sending emails for al most two decades now. You might think that we are pretty late on this feature, but there are a lot us who don't know much about composing an email that will actually be read and acted upon. A step-by-step reckoner...
To, CC and BCC, it all begins here
To is for the individual (or set of individuals) who is required to act on the email, CC (carbon copy) is for those who have to be kept in the loop, but are not required to act on it, or even acknowledge the receipt of the email; and bcc (blind carbon copy) is for sending the same email to people whose identities you don't intend to disclose to the people in the To and CC field. For example: If A wants B to delegate a job to C, B will write an email to C and cc A. However, if A doesn't want C to know that A is part of this development, B will bcc A.
The subject is the dodgiest part of composing an email as it decides whether the receiver will junk your email, read it later or open it instantly. So, keep the subject direct and noticeable. However, in an attempt to do this, don't write spam-worthy subjects like "Open Me", "Read it", "Hi".Examples of good subjects are "Urgent meeting at 3 pm", "Attn: Quarterly result", "Notice: New Rules for attendance". See Box above for more.