Ans- To answer this, I’ll have to start from the basics. So, there are two types of protocols which are POP3 and IMAP. These are used to retrieve E-mail from an E-mail server. POP3 here is a simpler version which means it only does the task of sending you the inbox mails. IMAP on the other hand synchronizes the mail received, which means you’ll receive the mail at the same time in the same place, no matter which device you use or use all devices at the same time. While Yahoo Mail supports both, it is highly recommended to use IMAP for which you have to do nothing as Yahoo Mail has a default set-up for IMAP.