RootComponent type.
If you want to know what does that mean 'RootComponent' and his code this article for you.
Solution.xml
RootComponent type="3" is for a Relationship
RootComponent type="4" is for a Attribute Picklist Value
RootComponent type="5" is for a Attribute Lookup Value
RootComponent type="6" is for a View Attribute
RootComponent type="7" is for a Localized Label
RootComponent type="8" is for a Relationship Extra Condition
RootComponent type="9" is for a Option Set
RootComponent type="10" is for a Entity Relationship
RootComponent type="11" is for a Entity Relationship Role
RootComponent type="12" is for a Entity Relationship Relationships
RootComponent type="13" is for a Managed Property
RootComponent type="20" is for a Role
RootComponent type="21" is for a Role Privilege
RootComponent type="22" is for a Display String
RootComponent type="23" is for a Display String Map
RootComponent type="24" is for a Form
RootComponent type="25" is for a Organization
RootComponent type="26" is for a Saved Query
RootComponent type="29" is for a Workflow
RootComponent type="31" is for a Report
RootComponent type="32" is for a Report Entity
RootComponent type="33" is for a Report Category
RootComponent type="34" is for a Report Visibility
RootComponent type="35" is for a Attachment
RootComponent type="36" is for a Email Template
RootComponent type="37" is for a Contract Template
RootComponent type="38" is for a KB Article Template
RootComponent type="39" is for a Mail Merge Template
RootComponent type="44" is for a Duplicate Rule
RootComponent type="45" is for a Duplicate Rule Condition
RootComponent type="46" is for a Entity Map
RootComponent type="47" is for a Attribute Map
RootComponent type="48" is for a Ribbon Command
RootComponent type="49" is for a Ribbon Context Group
RootComponent type="50" is for a Ribbon Customization
RootComponent type="52" is for a Ribbon Rule
RootComponent type="53" is for a Ribbon Tab To Command Map
RootComponent type="55" is for a Ribbon Diff
RootComponent type="59" is for a Saved Query Visualization
RootComponent type="60" is for a System Form
RootComponent type="61" is for a Web Resource
RootComponent type="62" is for a Site Map
RootComponent type="63" is for a Connection Role
RootComponent type="70" is for a Field Security Profile
RootComponent type="71" is for a Field Permission
RootComponent type="90" is for a Plugin Type
RootComponent type="91" is for a Plugin Assembly
RootComponent type="92" is for a SDK Message Processing Step
RootComponent type="93" is for a SDK Message Processing Step Image
RootComponent type="95" is for a Service Endpoint
Solution.xml
RootComponent type="1" is for a Entity
RootComponent type="2" is for a AttributeRootComponent type="3" is for a Relationship
RootComponent type="4" is for a Attribute Picklist Value
RootComponent type="5" is for a Attribute Lookup Value
RootComponent type="6" is for a View Attribute
RootComponent type="7" is for a Localized Label
RootComponent type="8" is for a Relationship Extra Condition
RootComponent type="9" is for a Option Set
RootComponent type="10" is for a Entity Relationship
RootComponent type="11" is for a Entity Relationship Role
RootComponent type="12" is for a Entity Relationship Relationships
RootComponent type="13" is for a Managed Property
RootComponent type="20" is for a Role
RootComponent type="21" is for a Role Privilege
RootComponent type="22" is for a Display String
RootComponent type="23" is for a Display String Map
RootComponent type="24" is for a Form
RootComponent type="25" is for a Organization
RootComponent type="26" is for a Saved Query
RootComponent type="29" is for a Workflow
RootComponent type="31" is for a Report
RootComponent type="32" is for a Report Entity
RootComponent type="33" is for a Report Category
RootComponent type="34" is for a Report Visibility
RootComponent type="35" is for a Attachment
RootComponent type="36" is for a Email Template
RootComponent type="37" is for a Contract Template
RootComponent type="38" is for a KB Article Template
RootComponent type="39" is for a Mail Merge Template
RootComponent type="44" is for a Duplicate Rule
RootComponent type="45" is for a Duplicate Rule Condition
RootComponent type="46" is for a Entity Map
RootComponent type="47" is for a Attribute Map
RootComponent type="48" is for a Ribbon Command
RootComponent type="49" is for a Ribbon Context Group
RootComponent type="50" is for a Ribbon Customization
RootComponent type="52" is for a Ribbon Rule
RootComponent type="53" is for a Ribbon Tab To Command Map
RootComponent type="55" is for a Ribbon Diff
RootComponent type="59" is for a Saved Query Visualization
RootComponent type="60" is for a System Form
RootComponent type="61" is for a Web Resource
RootComponent type="62" is for a Site Map
RootComponent type="63" is for a Connection Role
RootComponent type="70" is for a Field Security Profile
RootComponent type="71" is for a Field Permission
RootComponent type="90" is for a Plugin Type
RootComponent type="91" is for a Plugin Assembly
RootComponent type="92" is for a SDK Message Processing Step
RootComponent type="93" is for a SDK Message Processing Step Image
RootComponent type="95" is for a Service Endpoint
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