Story ,Task ,sub task

[Abida Rana]

Hey !! 
I wanna discuss that if we want to add stroy and add subtask for stroy . but why we need to assign a stroy ?? 

i need to add story as a heading of any task and add subtask in it . but in story also have a assignee option. why we need to assign story

[Nic Brough -Adaptavist-]

A story (or task, or issue, or bug, etc) is what your users work on, so it's a good idea to assign them to someone to get them dealt with.

Sub-tasks are a way of breaking up a parent into more manageable pieces so that other people can be assigned different parts and/or it makes it easier to think of in pieces, and/or you have attributes that aren't global for the story, and/or <several other reasons>

[Abida Rana]

if we want to add heading of some task and with in we want to add some tasks, what i sthe way, 

beacause if a take story as a heading and add sub task in it, but also need to assign story to some one, but i want to use story just for heading of task.. 

and want to show in report ,, issue is this if i am not assigning story to any one and there are sub task in story and sub task are assgin to user, the sub task are not showing in report.

i want to show this in reprt ..

and please tel me the use of epic also, why we use , 

[Nic Brough -Adaptavist-]

You don't have to assign a story, but in most cases, you probably should.

I don't know what "report" you are using.  Some will show you sub-tasks, some focus on the overall estimatable work items of stories.  Without knowing what you are using to report, I can't tell you more.

Epics are for grouping stories together in logical groups

[Abida Rana]

i am usign timetracking report.. if my stroy is in not in progress or not assigned no any one , then the stoey sub task are not show in the reprt