What is a protocol?
A protocol is a set of rules that governs how data transfers between devices occur.
Compare and contrast IMAP4 to POP3. Which one has more features?
IMAP4 is more widely used than POP3 but POP3 has more features. IMAP4 downloads files while POP3 accesses files in an email server. IMAP4 is suited for one device while POP3 is suited for multiple devices.
What is the default port number for POP3, IMAP, and SMTP?
The default port number for POP3, IMAP, and SMTP are 110, 143, and 25, respectively.