1. In a data processing system including memory means for storing data and active tasks, CPU means responsive to active tasks for operating on the data, mass storage means for storing inactive tasks, and keyboard means for entering user commands for interactively controlling execution of the active tasks, task control means for controlling the interactive, concurrent execution of a plurality of tasks, comprising: task loader means responsive to a task load request resulting from user commands or the execution of presently active tasks for transferring a corresponding inactive task from the storage means to the memory means to become an active task to be executed, memory manager means responsive to operation of the task loader means for assigning a corresponding task node space in the memory means for storing the task to be transferred into the memory means, task manager means, including task control block means responsive to the task load request for creating a task control block corresponding to the task to be transferred from the storage means to the memory means to become an active task, each task control block containing information used by the task manager means in controlling execution of the corresponding active task, and generating a corresponding task control block identification and writing the task control block identification into the corresponding task node space in the memory means, each task control block identification linking the task to the corresponding task control block, and task queue means for ordering the sequence of execution of the active tasks wherein each active task is a member of one of a plurality of priority levels, including a task queue for each priority level, wherein the task control block of each active task resides in the task queue corresponding to the priority level of the task, and the task control blocks reside in each task queue in a sequence determined by the status of execution of the corresponding active tasks, and wherein the task manager means is responsive to the priority level and status of each active task to write the corresponding task control block into the corresponding sequential location in the task queue corresponding to the priority level of the task.