The ServiceNow REST API is a web service that allows you to interact with the ServiceNow platform using HTTP requests and responses. The ServiceNow REST API supports the following methods:
POST: This method allows you to create a new record or execute an action on the ServiceNow platform. For example, you can use the POST method to create an incident or run a script.
GET: This method allows you to retrieve information from the ServiceNow platform. For example, you can use the GET method to get the details of a user or a table.
DELETE: This method allows you to delete a record or a resource from the ServiceNow platform. For example, you can use the DELETE method to delete an attachment or a workflow context.
PUT: This method allows you to update a record or a resource on the ServiceNow platform. For example, you can use the PUT method to update the state of a task or the value of a system property.
PATCH: This method allows you to update a record or a resource on the ServiceNow platform by sending only the changes. For example, you can use the PATCH method to update the short description of an incident or the order of a module.
The method COPY is not part of the ServiceNow REST API. There is no COPY method in the HTTP protocol. To copy a record or a resource on the ServiceNow platform, you need to use the POST method with the clone action.
Reference:
ServiceNow REST API overview
ServiceNow REST API methods
[ServiceNow REST API actions]

https://developer.servicenow.com/dev.do#!/reference/api/rome/client
The GlideUser object (g_user) is part of the client-side scripting API that provides information about the current user and the user's preferences. It can be used in Client Scripts and UI Policies to customize the user interface based on the user's role, language, time zone, etc. The workflow.scratchpad object is only available in Workflow scripts, which are used to automate processes on the platform. The current and previous objects are only available in server-side scripts, such as Business Rules and Script Includes. The GlideSystem object (gs) is also a server-side object that provides methods for logging, debugging, date and time calculations, etc.
Reference:
[GlideUser object (g_user)]
[Workflow scripts]
[Business Rules]
Script Includes
[GlideSystem object (gs)]

https://developer.servicenow.com/dev.do#!/learn/courses/sandiego/app_store_learnv2_learnmore_sandiego_learn_more/app_store_learnv2_learnmore_sandiego_form_and_list_layouts/app_store_learnv2_learnmore_sandiego_what_is_form_designer The Form Designer is a tool that allows you to create and customize forms on the ServiceNow platform. The Form Designer has four main components:
Form layout: The form layout shows the preview of the form and allows you to drag and drop fields, sections, and related lists onto the form. You can also resize, reorder, and delete the elements on the form layout.
Page header: The page header shows the name of the table and the form that you are editing. You can also access the form properties, save the form, and switch to the form view from the page header.
Field navigator: The field navigator shows the list of available fields for the table and allows you to search, filter, and add fields to the form. You can also create new fields and edit existing fields from the field navigator.
Schema map: The schema map is not part of the Form Designer. The schema map is a separate tool that shows the relationships between tables and fields on the platform. You can access the schema map from the System Definition > Tables module or from the context menu of a table.
Reference:
[Form Designer]
[Schema map]

It is possible to change an application's scope in ServiceNow, either from global to private or from private to global. However, changing the scope of an application may affect its functionality and compatibility with other applications. Therefore, it is recommended to test the application thoroughly before and after changing its scope.
Reference:
How To Change Application Scope In ServiceNow - YouTube
How to move Custom Scoped Applications bettween instances - ServiceNow
Steps to switch a scoped application from your company's application repository to update sets - ServiceNow How to change the application (scope) of a SLA Definition without needing to recreate the SLA Definition - ServiceNow Advantages of Scoped Applications in ServiceNow - QualityClouds