We send our donors once a year an email and ask them to become members. The email contains a link with a contact checksum that directly leads them to a contribution page, where they can select their membership and do the payments.
And our existing members we send a similar email and ask them to renew.
Both pages generate an email receipt using the template Memberships - Receipt (on-line) Is it possible to make a difference between the new and the already active members?
The CiviCRM version is 4.7.26.