Any business communication revolves around email communication and it is difficult to figure out how effective your email is. You are filled with these questions like, did he receive my email, did it open it? What if he didn't receive my email?
Email insights gives you the following details:
It gives you the email opened/clicked time in the record details page.
Furthermore, when email insights is enabled, Email status field gets added to a record which captures the exact status of the emails.
The email status field can tell you if the email was opened, clicked or bounced.