ODBC means Open Database Connect. These are special links to join Microsoft programs like Access, Transactin Server, to powerful Databases like SQL or Oracle. I expect you have seen the ODBC button in control panel. You will only need it if you have to connect to a big database like ODBC
OLE means Object Linking and Embedding. An Excel chart is the best example, create a chart in Excel. If you double click it you get differnt toolbars. The point is that graph chart features are embeddedinside a spreadsheet. Microsft use OLE widely to save re-inventing the wheel. Why make Excel create a chart, when there is alread a Microsoft Chart engine available.
