what is the major function of Primavera software?how many levels in primavera?

The major function of primavera is to support your planning process.
primavera is a powerful planning tool use in all over the world to plan projects mainly in terms of time, resources and cost.
As far as levels of planning is concerned different planners, specialist and scholars give different levels of planning.
I mean no of levels.
But i personally feel that it has five levels.
1- scope planing -------- here we define the major milestones or deliverable s of the project.
2- break up of scope---- this is nothing but making of WBS (work break down structure).
here you make different work groups or packages , which you have to do for achieving your milestones.
3- insertion of activities ----------------here you insert activities in there work packages.
4- resource loading ------------ on the fourth level you load your activities with resources which are required to complete all those activities which you have mentioned earlier.
5- cost loading----------- in the last you put cost or more better to say expected or budgeted cost needed to complete all the activities you have define in your project.
here you can define both the cost direct and indirect costs of your project.

Thank you Muhammad for your great question and also thanks to Hafiz for his good answer.
Primavera is a great ,powerful and amazing software in the sector of project planning and scheduling,and I would like to say that it is of great importance for any project manager to manage his project effectively and uniquely to achieve and handle deliverables successfully on time .under budget and to the specifications.
The process of applying Primavera for planning and managing any project consist of the following steps and levels:
1- Definition of the preferences and the defaults of the project2-definition of the work break down structure (WBS)3-Adding activities ,work packages and the milestones
3- developing the schedule net work diagram using the activities sequences ,activity duration and relationships
4- assigning resources to all the activities in the WBS .
5- Adding the quantities of the the resources from the bill of quantity which must be identified already using usually Excel program and as a result the activities costs will be resulted.5-Perform scheduling using the scheduling tool to develop the project schedule.
6- Adjust the schedule by using the resource leveling techniques, the schedule compression and the adjustment of lags and leads .
6- After that you will have your program ready for monitoring and controlling schedule ,cost and risk all through the project duration.
Thank you Best regards

Whatever said earlier is not enough for Oracle P6, which has still much more. But the great functions that make Oracle P6 unique in the market are1- Create Reflection, Check-in & Check-out, Global Change and Financial Periods. And these helped me a lot managing more than one project at different locations of the city even without web based application.

i see whatever has been described above is related to the major functionality levels and breakdowns of the project as a whole If you are asking about how many level depth primavera can go then I have An alternate answer to that Sometime the client says that they need a7level schedule ..
Then it means that you have to breakdown all activities into seven levels in the program It needs a bit more space to understand the meaning of levels in primavera I have created projects upto10 levels during these periods

On top of above - the maximum levels possible in WBS is50.

all of the above but on top of that P6 offers the potfolio analysis, capacity planning resource management and integration with major cost/resource management systems like SAP