Reference to the document's Style Gallery.
[Visual Basic .NET] Public ReadOnly Property StyleGallery As IStyleGallery
[C#] public IStyleGallery StyleGallery {get;}
Product Availability
Available with ArcGIS Desktop.
Remarks
The StyleGallery is an object that manages styles. Styles are a collection of predefined colors, symbols, properties of symbols, and map elements that are used to create maps. Styles help organizations follow a mapping standard and help promote consistency in mapping products.
The StyleGallery is the object underlying the Style Manager window in ArcMap. There is one StyleGallery object per application and it is global. Instantiating a new StyleGallery object really finds the one created by the application.