Remove Empty Lines

In short Removing empty lines strips out blank lines and lines containing nothing but whitespace, which are the ones that look empty and are not. That distinction is the reason a tool is worth using: a line holding a single space or a tab is invisible in an editor, survives a manual scan, and breaks a CSV import or a line count all the same. The alternative behaviour — collapsing runs of blank lines into one rather than removing them all — is the one you want for prose, where the blank lines are paragraph breaks and only the accidental doubles are a problem. Removing every blank line from an article joins all the paragraphs into a single block. The usual sources of the problem are pasting from a PDF, where every page break leaves a gap, and exporting from a spreadsheet, where trailing empty rows become trailing empty lines that most tools then count as data. Combined with the duplicate-line remover this is the standard first step on any list that came from somewhere else.