Plaifah Wongamonjak, known professionally as Plaifah.postcard, is a Thai illustrator and visual artist who holds a degree in Communication Design from the Faculty of Architecture and Design at King Mongkut's University of Technology Thonburi (SOA+D).

Her work is distinctly characterized by the expressive use of acrylic paint, marked by a bold and confident brushstroke technique paired with a soft and delicate color palette — a combination that creates a warm, intimate atmosphere uniquely her own.