Color vision differs from person to person
Not everyone sees color the same way. By commonly cited estimates, about 1 in 12 men and 1 in 200 women of Northern European descent have some form of red-green color vision deficiency. Protan and deutan types make reds and greens hard to tell apart, while the much rarer tritan type affects blues and yellows.
Design tips for everyone
Don't rely on color alone to carry meaning: add labels, patterns, icons or line styles to charts and maps. Make colors differ in lightness as well as hue, and avoid pairing red and green, or blue and purple, as the only difference. Checking your palette here before you publish makes your work easier to read for everyone.
About the simulation
The simulation is an approximation based on the model by Machado, Oliveira and Fernandes (2009). Real color vision varies between individuals and the result also depends on your screen settings, so use it as a guide rather than an exact reproduction.