Density is defined as how thick or thin you want your hair to be. The standard and most popular choice is 130% which is Medium Density. You can see examples of the density - Click Here.
Google's Gmail Web-based email service runs on the Internet Message Access Protocol system, but it also offers Post Office Protocol mail server access.
IMAP and the earlier POP3 (Post Office Protocol) are the two most prevalent standard protocols for email retrieval, with many webmail service providers such as Gmail, Outlook.com and Yahoo! Mail also providing support for either IMAP or POP3.