I felt rather bad about Mali's flag last week without any clues about how to distinguish it from, oh, say, Guinea's. So here we go with flags in red, green, and yellow. Most of them are African.
Side by side the difference is obvious:
Mali has green on the hoist side and
Guinea has red on the hoist side.
(I have a flag of Guinea, btw, in my collection, one of the random ones I came across--and yes, it took me a while to be sure which flag I had in my hands).
Senegal looks like Mali but it has a green star in the central yellow stripe.
Cameroon looks like Senegal but it switches the red and yellow and has a yellow star in the central red stripe.
Republic of the Congo is the only one with a diagonal, so that makes it stand out. Of course you don't want to confuse it with its larger neighbor, the Democratic Republic of Congo which has a diagonal but the flag is in red, blue, and yellow and has a star.
Lithuania is the only one with a (horizontal) green stripe in the middle.
Ghana and Bolivia have the same pattern of horizontal stripes: red, yellow, green (top to bottom). Ghana has a black star in the central stripe and Bolivia has a coat of arms in the central stripe.
Benin and Guinea-Bissau have similar structural design, with a vertical stripe on the hoist side and two horizontal stripes next to it.
Benin has green on the hoist side and no star.
Guinea-Bissau has red on the hoist side and a black star.
Now, in a very perverse mnemonic: Guinea and Guinea-Bissau both start with the letter "G" but they do NOT have green (also beginning with "g") on their hoist side. Tsk, it would be so much easier for anglophones if they did. But they don't. Instead they have red. But, if you have studied heraldry, you know that the color red is called "gules" and it does start with the letter "g." That, however, is too clever by half and I have probably confused you even further.
São Tomé and Príncipe has two distinguishing characteristics: a red triangle and two black stars.
Togo, like Puerto Rico and Cuba, has five stripes in a three dark and two light pattern (only those countries share the colors red, white, and blue). Togo is like Chile in having a canton with a star, and is the only one in this group that has that feature.
In flag terminology, a canton is the upper left (hoist) quarter of a flag. The United States flag has a blue canton with white stars.
Among these flags, Burkina Faso stands out for having no yellow stripe.
I almost excluded Ethiopia because it has blue in its design. I have allowed black stars but otherwise stuck to the three-color scheme. Still, because it has green, yellow, and red stripes, I included it. The blue circle with yellow radiant star makes it stand out.
If you are like me, you won't be carrying all this around in your head. But you now have an easy reference for distinguishing flags in this color combination.
And that is my warm-up for tomorrow's geography blogging.
Any bets on where I'll go? I've already prepared the graphics, so I'm committed.