I'm going through access rules tutorial \https://www.odoo.com/documentation/14.0/developer/howtos/rdtraining/B_acl_irrules.html#access-rules

please someone tell me how to paste XML code here in a way it doesn't trim the tags away. I can't even show example of the rule, but you will find it in the link above

It's written that this rule 

Only applies to the “create”, “update” (write) and “delete” (unlink) operations: here we want every employee to be able to see other users’ records but only the author / assignee can update a record.

I don't get it. We haven't even written anything about create/update/unlink in the rule, why does it apply to those operations? Also, the code says (I think) that when the domain is met, read permission should be false, which doesn't make sense at all.

Please explain.