People/Group field in SharePoint allow us to keep adding the existing user(s) or group(s) into the document library or list item. Let’s think, I have a list where one field name i.e. Assigned To (reviewer) is type of People/Group. Objective is when I assign someone to review the list item, and then an email notification needs to be fired up to that reviewer.
In other words, you have to find that person from the UserCollection list in SharePoint and send an email to that associated person.
Now once you assign one person on this field, you will found how the SharePoint display his/her name in the New/Edit OTB form and it is like DOMAIN\LOGINNAME. So if your domain name is SP-SERV and your name is Himadrish Laha, it will be looks like SP-SERV\Himadrish Laha.
Below the simple code I have used to fetch the string data and it returns me something else which I found in the debugging mode “1;#SP-SERV\\kiran” (here I have added user Kiran). When I have added my name it looks like “16;#SP-SERV\\Himadrish Laha“. String represent is kind of <UserID>;#<UserLoginName>.More difficult for you to work.

