Taking a COVID-19 test at home seems simple enough: If you get a line, you're positive for the coronavirus. But what if your results aren't so obvious? For instance, if you only get a very faint line ...

The results of a home pregnancy test aren't always black or white (or clearly blue or pink!). If you see a faint line on a pregnancy test, especially if you took the test correctly, you're probably ...

You squint. You hold it up to the light. You take it to the window, then back to the bathroom. You snap a photo and enhance the brightness. Is that really a line? Or just your desperate hope ...