Common loanword used in business, IT, and everyday contexts for a piece of work or assignment.
I haven't finished today's tasks yet.
He handles a lot of tasks every day.
Let's divide up the project tasks.
The manager assigned a task to each member.
I completed all the tasks.
I'm tackling a new task.
There are still a few tasks left.
作業 refers to hands-on or procedural work being carried out, while タスク is a more general term for any assigned item of work, physical or not.
タスク usually refers to a smaller, specific assignment, whereas ジョブ can denote a larger unit of work or, in computing, a whole batch process.
Used when referring to individual tasks or items of work, especially in a project or business context.
Borrowed from English 'task'.