The red, green, black and white flag introduced under ... with Syria's Kurds flying their red, white, green and yellow flag in areas they control.

"We are all guilty of telling white lies ... this could be a red flag. This lack of commitment could cause problems down the line. Yellow flags vs. red flags Yellow flags are also warning signs ...

What do red and yellow flags mean at Florida beaches? Florida beaches tend to use four colors to tell beachgoers current tide and surf conditions: Red, yellow, green and purple. Here's what they mean.