Form handlers are the best option if you want to integrate with a third-party system, such as a payment gateway, a survey tool, or a webinar platform. Form handlers allow you to post data to more than one location, so you can send the prospect information to Marketing Cloud Account Engagement and to the external system at the same time1. You can also use form handlers to connect Marketing Cloud Account Engagement to your existing forms on your website or other platforms

Explanation
The difference between a visitor and a prospect is that a visitor is an anonymous person who visits your website, while a prospect is a known person who has an identified email address. A visitor becomes a prospect when they fill out a Marketing Cloud Account Engagement form, click on a tracked link in an email, or are manually imported into Marketing Cloud Account Engagement. A prospect does not necessarily have an opportunity, a Marketing Cloud Account Engagement form submission, or an assigned user, but a visitor does not have any of these either. References Visitors and Prospects

You can define a user's role in two ways: during the import process or directly from the user record. During the import process, you can assign a role to multiple users at once by using a CSV file. Directly from the user record, you can edit the role of a single user by selecting it from the dropdown menu. You cannot define a user's role from the list view or through an automation rule. Reference: Create and Edit Users, Import Users

Explanation
When a user creates and resumes a new automation rule, the rule will continuously look for prospects who match the criteria (B) and evaluate their entire prospect database for matches. These are the characteristics of automation rules in Account Engagement, which are different from segmentation rules that run only once.
The rule will not run once and must be re-run for prospects to match again (A), nor will it unmatch prospects that no longer match the criteria (D). Unmatching prospects is only possible with dynamic lists, not automation rules. References: Using Account Engagement Automation Rules vs. Salesforce Flows

Explanation
The baseline grade assigned to a prospect is D. A Marketing Cloud Account Engagement grade is a rating based on how well a prospect's profile matches your ideal customer profile. The prospect rating is expressed as a letter grade that ranges from F (worst) to A+ (best). Marketing Cloud Account Engagement assigns an initial grade of D to all prospects. You can then adjust the grade up or down based on the prospect's attributes, such as industry, job title, company size, location, etc. The grade reflects how well the prospect fits your target market and how qualified they are for your product or service. You can create different grading profiles for different personas or segments, and assign prospects to profiles based on certain criteria.
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