Kubectl is a command-line tool used to manage and control Kubernetes clusters. It allows users to deploy applications, inspect and manage cluster resources, and view logs. With kubectl, you can perform various operations like scaling applications, rolling out updates, and troubleshooting issues within your cluster. The tool communicates with the Kubernetes API to execute commands and retrieve information about the cluster's state. It supports a wide range of commands and options, making it essential for developers and system administrators working with containerized applications in a Kubernetes environment.