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This restriction uses information in the student’s user profile to control access. It is unlikely to be useful in most cases, since most student profiles contain limited information.This can be used to restrict access to specified individuals, by matching against their email address (which is unique to each individual).
Moodle will add the restriction to the form as follows:
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The settings are:
Field from the user’s profile to check (usually ‘Email address’)
Nature of the comparison: “is equal to”, “contains”, etc.
The text to compare against the profile field
Only users whose profile fields match the specified comparison will be able to access the activity. This is useful when providing resources to individual students with specific requirements.
IMPORTANT: Always close the eye-icon 
, to hide the criteria when specifying individual students, so that their identities are not visible to other students. This is especially important when restricting access to students with Inclusion Plans (IPs).
Restriction set
This is not really a restriction type, but simply a framework for adding hierarchy to your restrictions.
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