The purpose of the VLOOKUP function is simple: it looks up data in tables and returns results from a different column. So if you have a table of products, for example, you could ask VLOOKUP to return the price for an item given the ID of the product.

But VLOOKUP is more than just that; it is the gateway to real Excel knowledge. The VLOOKUP function contains everything that a function can throw at you: multiple required parameters, optional parameters with defaults, and needs both ranges and numeric data in its input strings. If you can master this function, you can master ANY other function in Excel.
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