The Inbox is the default storage folder for all incoming electronic messages. When a new message is received, it is automatically routed here unless specific filters are set to move it elsewhere. It serves as the primary repository where users can read, manage, and organize their correspondence. 

Once you click "Send" on a reply, it is treated as an outgoing message. Standard email clients automatically move a copy of any message you have sent—including replies—into the Sent folder to maintain a record of your correspondence.

• In emails, CC stands for Carbon Copy. 
• It is an email feature that allows you to send a copy of a message to recipients other than the primary one listed in the "To" field. 

A Mailbox is the digital storage area on a mail server where an email account's messages are delivered and kept. It acts as a central repository, often organized into sub-folders like the Inbox, Sent Items, and Drafts to manage incoming and outgoing communication. 

• Primary Function: It is a software application designed to send, receive, and manage user emails.
• Protocol Support: It uses protocols like IMAP, POP3, and Exchange ActiveSync to communicate with an email server.
• Personal Information Manager: Beyond email, it functions as a comprehensive manager for calendars, tasks, contacts, and notes. 

• The email servers are All of these (Gmail, Hotmail, and Yahoo Mail). 
• Gmail, Hotmail (now Outlook.com), and Yahoo Mail are widely recognized as major webmail service providers that operate their own mail servers for sending, receiving, and storing emails. 

Spam: This is the common term for unwanted, unsolicited, and often commercial messages sent in bulk to a large number of recipients.

UBE (Unsolicited Bulk Email): This is the formal, technical term for spam.

Junk Mail: Another common term for unwanted email, often used interchangeably with spam. 

• An email bounce usually occurs due to issues like a bad domain name or a bad user account name.
• However, a temporary issue like the domain server being down is not a major or common cause for permanent email bounce.