From Adobe Acrobat to free online editors and built-in tools, here’s how to merge multiple PDFs into one document.

You can use Excel's VSTACK and HSTACK functions to append data in regular cell ranges, Excel tables, or named ranges. into cell E1 stacks the three arrays in the cell ranges A2 to C6, A9 to C13, and ...

If you need to find a particular value in an Excel sheet, the quickest way is to use a lookup formula. The most popular functions to use in these formulas are VLOOKUP and HLOOKUP, which search across ...

A few years ago, I had lunch with the head of a major motion picture studio, who declared that his central problem was not finding good people—it was finding good ideas. Since then, when giving talks, ...

The proton gradients that power respiration are as universal as the genetic code itself, giving an insight into the origin of life and the singular origin of complexity. Why do virtually all cells ...