VLOOKUP vs LOOKUP in Libre Office Calc

VLOOKUP acts on a multi-column array as compared to LOOKUP that works on two independent columns (or rows) , and hence it requires the index for the result column as a third argument.

However VLOOKUP has an advantage over LOOKUP and it should be preferred in general, when possible. Its last argument, a boolean TRUE or FALSE, determines if the search keys are ordered or not. In many cases these would not be ordered in the original spreadsheet, and hence VLOOKUP(cell,array,index,FALSE) offers a clear advantage over LOOKUP(cell,keys,values)