The ability to recognize a customer who has already been on the site to facilitate contact. To maintain the continuity of contact, so that he would not have to write anew and fill in forms.
That he would feel taken care of.
Remembering user form data:
1) name
2) e-mail
In order to fill in forms for people who have used it before.
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It can also be used to greet:
"Hello Jack again"
2 years ago