Define the following organizaions as per the requirement of business
i. Business group
ii. Legal Entity
iii. Operating Units
iv. Organization

External organizations (for example, tax offices, insurance carriers, disability organizations, benefit carriers, or recruitment agencies)
Internal organizations (for example, departments, sections or cost centers)

Creating an Organization
1. Enter a name for your organization in the Name field. A check is performed to see if organizations with the same name already exist.
All Oracle applications you install share the information entered in the Organization window. Therefore organization names must be unique within a business group, and business group names must be unique across your applications network.
You can create two organizations with the same name in different business groups but this can cause confusion later, if the HR: Cross business group profile option is set to Yes and you decide to share certain information across all business groups. If you decide to create two organizations with the same name, be sure that this will not cause you problems in the future.
2. Optionally, select an organization type in the Type field.
Organization types do not classify your organization, you use them for reporting purposes only. The type may identify the function an organization performs, such as Administration or Service, or the level of each organization in your enterprise, such as Division, Department or Cost Center.
3. Enter a start date in the From field. This should be early enough to include any historical information you need to enter.
Note: You cannot assign an employee to an organization before the start date of the organization.
4. Enter a location, if one exists. You can also enter an internal address to add more details such as floor or office number.
If you are using Oracle Payroll in the US, every organization to which employees can have assignments, including business groups, must have on record a location with a complete address. This is because the system uses the location of the organization of the employee’s primary assignment to determine employee work locations for tax purposes. This does not apply to GREs, because the assignment to a GRE exists in addition to the assignment to an organization.
For Dutch users only, if you are setting up external organizations for a tax office, a social insurance provider or a private health insurance provider, you must enter the postal address and contact details using the NL_POSTAL_ADDRESS Location EIT.
Note: If you are an Oracle Inventory user, then you must not assign a location to more than one organization classified as an Inventory Organization.
5. Enter internal or external in the Internal or External field. You cannot assign people to an external organization.
Examples of external organizations that may require entry are disability organizations, benefits carriers, insurance carriers, organizations that employees name as beneficiaries of certain employee benefits, and organizations that are recipients of third party payments from employees’ pay.

 
 
Inventory : Setup -> Organizations -> Organization
 

Enter Organization Classifications & Additional Information
1. Business Group

Business Group Information.
Budget Value Defaults.
Work Day Information.
Benefits Defaults.
PTO Balance Type.
Recruitment Information.
Payslip Information.
Self Service Preference Information.
2. Attaching Set of Books to Legal Entity

 

3. Attaching Set of Books & Legal Entity to Operating Unit

4. Attaching Operating Unit to organization
Use the Locations window to define ship–to, bill-to, receiving, office site, internal site & other location information for Purchasing documents.

Locations are shared across Business Groups in HRMS and with two other Oracle applications: Inventory and Purchasing. HRMS does not use some of the fields in the Location window. These fields are disabled for HRMS users. For example, the Legal Address check box is read-only and supports future functionality in Oracle Financials.
Header
Uncheck the Global check box if you want the location to only be available within the default Business Group of your current responsibility. Accept the default if you want the location to be a global location and therefore available to all Business Groups. If you are setting up a global location, the location name must be unique across all Business Groups. If you are setting up a location for one Business Group, the location name must be unique within that Business Group and all global locations, but does not have to be unique across all Business Groups.
Note: You cannot amend the Global check box once you have set up your location.

Address Details Tab

Select a national address style from the list. If a local address style exists for your country, it is displayed as the default. Otherwise, the international style is displayed.
Shipping Details
Selecting the check boxes means that you are making the location Name a valid location in the list of values on a Purchasing
document. For example, selecting Ship–To Site makes the location  Name a valid choice in the list of values for the Ship–To field on a purchase order header. Note that if you define a default Ship–To or Bill–To Location in the Supplier–Purchasing region of the Financials Options window for your organization, that is the location that defaults onto your purchase orders. But if you wanted to change that default, the location Name that you define here and enable as a Ship–To or Bill–To site is available in the list of values for you to choose from in the Ship–To or Bill–To fields.

Contact: Optional contact name for the location Name.
Ship–To Location : Its the receving dock. Usually the same as the location Name. You could select a separate, previously defined Ship–To Location—for example, if you wanted to create a location Name, Office A, and specify Receiving Dock A as its Ship–To Location. Note, however, that once you specify a separate Ship–To Location, you can no longer enable the location Name as a Ship–To Site. In this example, Receiving Dock A is the ship–to site for Office A; therefore, Office A itself cannot also be the ship–to site.
Ship–To Site: Is this location is a receving dock. Select this option to make the location Name a valid ship–to organization on a purchase order or requisition.
Bill–To Site: Select this option to make the location Name a valid bill–to site. The Bill–To Site, which is used by Payables, is specified on a purchase order header.
Receiving Site: Select this option to make the location a valid receiving Location when creating a receipt or receiving transaction.
Office Site: Select this option to indicate that this location Name is an office site, such as a field office.
Internal Site: Select this option to make the location a valid internal ship–to location when creating an internal requisition.
Other Details
Inventory Organization: Select an inventory organization within which this location will be available in the list of values on a Purchasing document. By selecting no inventory organization, this location becomes available on Purchasing documents
in all organizations.
EDI Location: If you use Electronic Data Interchange (EDI) to receive Advance Shipment Notices (ASNs) or ASNs with billing information (ASBNs), enter a defined location. This location should match the ship-to location specified on an ASN or ASBN

You can define and update material planners or planning entities for the current organization and assign them to inventory items at the organization level.

To define and update material planners or planning entities:
1. Navigate to the Planners window.
2. Enter a unique planner name. A planner can be a person or an entity, such as a department or a division. 3. Enter the electronic mail address of the planner.
4. Optionally, enter a date on which the planner becomes inactive. From this date on, you cannot assign this planner to an inventory item.

You must plan how Oracle Inventory represents your company’s inventory sites and business units. This includes defining organizations, locations, subinventories, and locators depending on your company structure. You also must plan how to implement certain parameters and what level of the structure controls them.

Multi-org often refers to an Oracle Applications setup used to enable multiple business units in a single install.  With multi-org, a business enterprise may set up multiple business units with differing sets of books, operating units, and legal entities all within a single instance.  With multi-org, goods my be sold out of one operating unit or legal entity and shipped out of another, and the system will process an intercompany sale to properly account for it.
Multi-org, however, should not be mistaken for installs with multiple inventory organizations.  You do not have to use Oracle Applications multi-org to support multiple inventory organizations if all the inventory organizations share the same set of books, operating unit, and legal entity.
Location:  A location is simply a name and address, and is assigned to an organization or used to indicate delivery information on a purchase order.  You may define as many locations as you like, but only one location may be assigned to an inventory organization. 
Business group is a group of companies that does business in different markets under common administrative or financial control whose members are linked by relations of interpersonal trust on the bases of similar personal ethnic or commercial background a business group.
Set of Books (SOB): The financial entity that represents the chart of accounts, fiscal calendar, and base currency.  The SOB is set up in the General Ledger.
Legal Entity Organization: An entity used to represent a legal company.  Fiscal and tax reporting are done at the Legal Entity level.
A legal employer is a legal entity that is responsible for employing people in a particular country. Therefore, if you employ people in a country, then you must have at least one organization classified as a legal entity and a legal employer.
The Configuration Workbench classifies an organization as a GRE/Legal Entity where your enterprise operates in a country, and classifies it as an Employer if you employ people in that country also. For example, you can have a legal entity in a country where you do business, but do not employ people in that country.
Operating Unit Organization: A business unit that shares a common Purchasing, Accounts Payable, Order Entry and Accounts Receivable setup.  An operating unit may consist of multiple inventory organizations, with multiple manufacturing sites, distribution centers, and sales offices, but they share a common sales order and purchase order system.  For example, a sales order may have lines shipping from different inventory organizations or a purchase order may have lines destined for different inventory organizations.
Inventory Organization:  An entity used to represent a manufacturing or distribution site.  Inventory organizations are where a user tracks on-hand balances, manufactures goods, and transacts the daily ins and outs of material movement.  An inventory organization is the lowest level entity for costing goods, planning material requirements, and securing system access.  Only a single address may be assigned to an Inventory Organization.  An inventory organization is assigned a Set of Books which determines the chart of accounts, fiscal calendar, and base currency for all financial and value added activities that occur within the organization. 
Inventory Organizations are also assigned to a Legal Entity Organization and an Operating Unit Organization.
A variation on the inventory organization is the master item organization.  Generally, with Oracle Applications a single inventory organization is created and designated at the master organization.  Items are defined first in the master organization, then enabled in other inventory organizations as necessary.  Some of the item attributes are set as controlled at the master organization and therefore the attribute values cannot be updated within individual inventory organizations.  Category sets may also be designated as master organization level.  Cross-references are also master level only or master level optional as well.  
Subinventory: Physical or logical locations for storing inventory.  Subinventories are generally defined to represent the main stores area as well as stocking points on the production floor.  Additional subinventories may be used to specify supply closets or cabinets and the cage area for discrepant material.  Subinventories are flagged as to availability for planning (nettable), reservations, and available to promise checks, thereby determining the availability of the material stored in the subinventory.  Subinventories are assigned material asset account numbers.  As goods move in and out of a subinventory a transaction posts to the asset account.
Stock Locator:  A physical area within a stockroom.  The stock locator is a key flexfield that is often defined as a multiple segment flexfield with the segments representing the physical layout of a stockroom.  For example, a stockroom may be laid out in rows of shelves with bins on the shelves, each numbered so that a row/shelf/bin combination would direct someone to a particular material storage compartment.  Such an implementation would define a locator flexfield as a 3 segment flexfield with segments for row, shelf, and bin.
Attachment of LE/OU/INV with BG
We never attach any LE/OU/INV with BG in front end…but its available in HR_ALL_ORGANIZATION_UNITS in column Business_Group_ID..so the question is from where it comes?
First we create a Business Group. When ever we create a business group the system creates an organization with type businessgroup and attach a business group ID ‘N’ which
is same as the organization ID for that Business group.
After that we attach the business group to a responsibility through the profile option HR : Business Group.
Next we create whenever we create a new LE/OU/Inv with one responsibility the system ‘ll attach the Business Group which is attached with the HR : Business group for that particular responsibility.

MTL_TRANSACTIONS_INTERFACE table is the Interface between non-Inventory applications and the Inventory  Transactions module.  In other words any other module other than Inventory that wants to update  Inventory has to come  through this table. Modules such as WIP (Work In Progress)  and OE (Order Entry) first pass their records to the  MTL_TRANSACTIONS_INTERFACE (MTI)for validation.

There is an Interface Manager called the Transactions Manager (INCTCM) which  reads records from this table, validates them and moves the successful  transactions onto MTL_MATERIAL_TRANSACTIONS_TEMP, and submits Transaction workers (sub-processes – INCTCW) which then processes these records through inventory. This process consists of data derivation, validation, and transfer of records from MTL_TRANSCTIONS_INTERFACE, MTL_TRANSACTIONS_LOTS_INTERFACE and MTL_SERIAL_NUMBERS_INTERFACE  into their respective TEMP (temporary) tables from where the transactions  processor processes them.
Both the Lots and Serial number tables above are used when items being  updated are under ‘Lot’ or ‘Serial’ number control. Example :- In the case  of an Sales Order, the item is being shipped to a client so the lot and serial  number if being used, this needs to be updated to show that it is no longer available in Inventory stock.
It is important to note that in general the processors will not move the transactions from this table if the following fields are not set as follows.
LOCK_FLAG = 2
PROCESS_FLAG = 1
transaction_mode = 3
Once the transactions have been passed to this table after initial validation by the Transactions Manager (INCTCM) from the MTL_TRANSACTIONS_INTERFACE a job id is attached and a Transactions Worker (INCTCW) is submitted by the INCTCM process in order to the get the records processed and moved to the MTL_MATERIAL_TRANSACTONS table.
This table is also used by Inventory Module and Purchasing module which writes directly onto this table for any transactions entered within itself and each transaction in turn through a process of strict validation.
Inventory Module Forms like Miscellaneous transactions writes directly into this table. The transactions which are done through these form are on-line processing. It is from here that the inventory quantities finally  get updated,serial/lot numbers get marked as being used.