It is basically the tracking or monitoring sent, delivered, opens, clicks and bounce of emails to follow up with leads, job applicants, and partners. Email Tracking can be termed as the checking of metrics of your email marketing campaigns to improve their quality, efficiency, and effectiveness.
There are many email tracking tools, three of them those who offer extra features and beyond basics are listed below:-
Snov.io’s unlimited email tracker offers emails open and clicks tracking as well as additional features. Features, for instance, are email scheduling, follow-up reminders, real-time notifications, and reports. It is a free and unlimited chrome extension that integrates seamlessly into Gmail. And it shows the exact number of clicks and opens, and help to enable or disable the monitoring of particular email addresses.
 MailTrack offers the same features as offered by snov.io but it adds a branding signature to each email sent. So recipients may find out that you keep track of opens and clicks. It offers some additional features too but with the paid plan. Therefore, you can see the opens information directly in the inbox and you can see if a person opened an email once or twice. email opens and clicks
This service allows you to monitor the way recipients interact with your attachments. The document can be viewed and how far a recipient has progressed in reading it. And, you can see the exact percentage of reading by this so that you can make changes if the recipients are responding to it half-way.
There are advantages and disadvantages of email tracking. Images can be blocked by default so that your pixel images that are invisible will not load. Blockers installed so that trackers are not able to see the email or cannot track your emails. It doesn’t work for groups as if you sent a single texted message to groups you cannot track the exact count of opens for a particular message.
https://en.wikipedia.org/wiki/Email_tracking
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