# Chapter 4. Devices and Queues

Once Vulkan is initialized, devices and queues are the primary objects used to interact with a Vulkan implementation.

Vulkan separates the concept of physical and logical devices. A physical device usually represents a single device in a system (perhaps made up of several individual hardware devices working together), of which there are a finite number. A logical device represents an application’s view of the device.

Physical devices are represented by `VkPhysicalDevice` handles:

    VK_DEFINE_HANDLE(VkPhysicalDevice)