Change sets are tools that allow administrators to move customizations such as fields, page layouts, profiles, permission sets, etc. from one Salesforce org to another. To use change sets, administrators need to establish a deployment connection between a source org (such as a sandbox) and a target org (such as production). Then, administrators can create an outbound change set in the source org that contains the components they want to deploy, and upload it to the target org. In the target org, administrators can view and validate the inbound change set before deploying it to their org. References: https://help.salesforce.com/s/articleView?id=sf.
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