If you’re involved in an email conversation in Microsoft Outlook and you want a fast and easy way to introduce other colleagues to certain parts of your message without having to start a new conversation, here’s how:
In the body of your email, type the '@' symbol followed by the person's name (their email address will be displayed if you've been in contact with them).
The mentioned person's name will be highlighted, and they will also receive a notification that they've been mentioned in the email, enabling them to join in.