The article discusses the evolution of avian brains and the need for a new nomenclature to reflect the current understanding of their structure and function. Traditional terminology, based on a 100-year-old theory by Edinger, has been shown to be incorrect in many respects. The avian cerebrum, which was previously thought to be primarily composed of basal ganglia, is now known to have a large pallial territory with cognitive functions similar to those of mammalian cortex. The Avian Brain Nomenclature Consortium has developed a new terminology to better reflect these findings. This new terminology includes terms that are more accurate reflections of the avian brain's homologies with mammalian brains and addresses the limitations of the classical view. The article also highlights the cognitive abilities of birds, which are often more complex than previously thought, and discusses the implications of these findings for understanding brain evolution and function.The article discusses the evolution of avian brains and the need for a new nomenclature to reflect the current understanding of their structure and function. Traditional terminology, based on a 100-year-old theory by Edinger, has been shown to be incorrect in many respects. The avian cerebrum, which was previously thought to be primarily composed of basal ganglia, is now known to have a large pallial territory with cognitive functions similar to those of mammalian cortex. The Avian Brain Nomenclature Consortium has developed a new terminology to better reflect these findings. This new terminology includes terms that are more accurate reflections of the avian brain's homologies with mammalian brains and addresses the limitations of the classical view. The article also highlights the cognitive abilities of birds, which are often more complex than previously thought, and discusses the implications of these findings for understanding brain evolution and function.