This author agreement combines a licence of copyright to the publisher with the payment of a fee by the publisher to the author.
A three versions - basic, standard and premium - require the author to deliver to the publisher a work of the defined description meeting the defined standards. Ancillary clauses cover the provision by the author of third party permissions, artwork, and other content for the book.
The agreement includes a set of warranties protecting the publisher, for example in the case of the author infringing another person's copyright. The warranties may be backed by an indemnity.
There is always a tension between the grant of a (potentially terminable) licence and the payment of a fee. It is more natural to combine a licence with an ongoing royalties obligation, and an assignment with the payment of a one-off fee. You should therefore think carefully before using this form of agreement rather than the licence/royalty or assignment/fee version.