# OLE Object Technology
The term OLE stands for Object Linking and Embedding. With object linking and embedding users can create document that contain embedded sections of documents from other applications and can treat those embedded document sections as though they were a natural part of the current documents. In OLE, we can embed items from other applications into our program.
Let's take an example of embedding, excel in the program. Embedding enables the user to edit the cells in our program when he double clicks the embedded item, excel is automatically opened and we can change the data there.
The user can also add text to the same document that contains the excel cells. In this way, the user can embed and coordinate forms from many different applications into one.
Here, the editor program(in which the OLE item appears) is called the container, because it can contain OLE items. The program responsible for actually maintaining those items- Excel here- is called the server OLE servers are registered with windows in a special file that we can edit with the windows utility re,edit.
-> Object Embedding :-
With this technique you can insert an object from one application ( the server application ) into another application ( the container application ). The inserted object is a copy of the original and can be manipulated and stored separately and apart from the original object.
For example, you can embed a range of cells from an excel worksheet in a word document. To edit the cells, you switch to excel by double clicking the embedded Excel object. If the container application supports in place editing, the menus of the server application in the container application.
In place editing is also known as in place activation. In this, the functionality of the server application is incorporated into the container, that enabling you to edit the object using the menus and tools of server application. For example if a word document contains a range of cells from an excel object replaces the word menus with excel menus, you can now edit cells without switching to another application.
When you save an embedded file, the following information is saved :-
1) The name of the application that created the object.
2) The objects data.
3) A meta-file image of the object.
-> Linking :-
The techniques is similar to embedding except that embedded data are also linked to the document in which they come. Changes to the object in the server application are selected automatically in the container application.
Linking does not store the object, it makes a reference. It is the object exposed by the server application, the time you open the document that contains the linked object, the container application contacts the server application which actually opens the most up to date version of the linked object.
Linked objects are not copies. They are the originals viewed from within different containers.
When you save a linked file, the following information saved :-
1) The name of the application that creates the object.
2) The file name of the object.
3) A meta file image of the object.
So, if we compare linking with embedding the embedding occupies more disk space because whenever an object is embedded, the object is saved to that application and it occupied more space according to these file or object.
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