The following language is added to the first section of the IG to introduce the concept of the scratchpad and explain why it's important. Throughout this IG, references to a "scratchpad" refer to an EHR capability where FHIR-structured data can be stored without the expectation of being persisted "permanently" in a FHIR server. The scratchpad can be thought of as a shared memory area, consisting of "temporary" FHIR resources that can be accessed and modified by either an app or the EHR itself.  Each resource on the scratchpad has a temporary unique id (its scratchpad "location"). A common use of the scratchpad is to hold the contents of a clinician's "shopping cart" – i.e., data that only exist during the clinician's session and may not have been finalized or made available through in the EHR's FHIR API. At the end of a user's session, selected data from the scratchpad can be persisted to the EHR's FHIR server (e.g., a "checkout" experience, following the shopping cart metaphor). This was discussed and voted on here:  https://confluence.hl7.org/pages/viewpage.action?pageId=104563953#SMARTWebMessagingBallotReconciliationCC20210212-1.1.1Scratchpad This was implemented here:  https://github.com/HL7/smart-web-messaging/pull/37