Once a form is published it has its own address that anyone can open — no Atwork account, no sign-in.

Copy the form's link and send it: in an email, on a page, in a chat message. It works anywhere.
Embed the form in your own site and it appears as part of your page, so people never leave. Handy for a contact page, a request form or an application.
Only the fields you put on the form. Not the sheet, not other people's submissions, not any other field on the same records. There is no way in from the form.
Worth stating plainly to anyone nervous about sharing it: a form is a one-way door into a single sheet.
A form only takes things in. Clients who should also see their own records need a portal instead.
Related: Build a form and collect responses · Automate the repetitive parts