R has 657 built-in color names. The function colors() will show all of them.
All these color names can be used in plot parameters like col=. The function
col2rgb() can convert all these colors into RGB numbers.
| white | aliceblue | antiquewhite | antiquewhite1 |
| antiquewhite2 | antiquewhite3 | antiquewhite4 | aquamarine |
| aquamarine1 | aquamarine2 | aquamarine3 | aquamarine4 |
| azure | azure1 | azure2 | azure3 |
| azure4 | beige | bisque | bisque1 |
| bisque2 | bisque3 | bisque4 | black |
| blanchedalmond | blue | blue1 | blue2 |
| blue3 | blue4 | blueviolet | brown |
| brown1 | brown2 | brown3 | brown4 |
| burlywood | burlywood1 | burlywood2 | burlywood3 |
| burlywood4 | cadetblue | cadetblue1 | cadetblue2 |
| cadetblue3 | cadetblue4 | chartreuse | chartreuse1 |
| chartreuse2 | chartreuse3 | chartreuse4 | chocolate |
| chocolate1 | chocolate2 | chocolate3 | chocolate4 |
| coral | coral1 | coral2 | coral3 |
| coral4 | cornflowerblue | cornsilk | cornsilk1 |
| cornsilk2 | cornsilk3 | cornsilk4 | cyan |
| cyan1 | cyan2 | cyan3 | cyan4 |
| darkblue | darkcyan | darkgoldenrod | darkgoldenrod1 |
| darkgoldenrod2 | darkgoldenrod3 | darkgoldenrod4 | darkgray |
| darkgreen | darkgrey | darkkhaki | darkmagenta |
| darkolivegreen | darkolivegreen1 | darkolivegreen2 | darkolivegreen3 |
| darkolivegreen4 | darkorange | darkorange1 | darkorange2 |
| darkorange3 | darkorange4 | darkorchid | darkorchid1 |
| darkorchid2 | darkorchid3 | darkorchid4 | darkred |
| darksalmon | darkseagreen | darkseagreen1 | darkseagreen2 |
| darkseagreen3 | darkseagreen4 | darkslateblue | darkslategray |
| darkslategray1 | darkslategray2 | darkslategray3 | darkslategray4 |
| darkslategrey | darkturquoise | darkviolet | deeppink |
| deeppink1 | deeppink2 | deeppink3 | deeppink4 |
| deepskyblue | deepskyblue1 | deepskyblue2 | deepskyblue3 |
| deepskyblue4 | dimgray | dimgrey | dodgerblue |
| dodgerblue1 | dodgerblue2 | dodgerblue3 | dodgerblue4 |
| firebrick | firebrick1 | firebrick2 | firebrick3 |
| firebrick4 | floralwhite | forestgreen | gainsboro |
| ghostwhite | gold | gold1 | gold2 |
| gold3 | gold4 | goldenrod | goldenrod1 |
| goldenrod2 | goldenrod3 | goldenrod4 | gray |
| gray0 | gray1 | gray2 | gray3 |
| gray4 | gray5 | gray6 | gray7 |
| gray8 | gray9 | gray10 | gray11 |
| gray12 | gray13 | gray14 | gray15 |
| gray16 | gray17 | gray18 | gray19 |
| gray20 | gray21 | gray22 | gray23 |
| gray24 | gray25 | gray26 | gray27 |
| gray28 | gray29 | gray30 | gray31 |
| gray32 | gray33 | gray34 | gray35 |
| gray36 | gray37 | gray38 | gray39 |
| gray40 | gray41 | gray42 | gray43 |
| gray44 | gray45 | gray46 | gray47 |
| gray48 | gray49 | gray50 | gray51 |
| gray52 | gray53 | gray54 | gray55 |
| gray56 | gray57 | gray58 | gray59 |
| gray60 | gray61 | gray62 | gray63 |
| gray64 | gray65 | gray66 | gray67 |
| gray68 | gray69 | gray70 | gray71 |
| gray72 | gray73 | gray74 | gray75 |
| gray76 | gray77 | gray78 | gray79 |
| gray80 | gray81 | gray82 | gray83 |
| gray84 | gray85 | gray86 | gray87 |
| gray88 | gray89 | gray90 | gray91 |
| gray92 | gray93 | gray94 | gray95 |
| gray96 | gray97 | gray98 | gray99 |
| gray100 | green | green1 | green2 |
| green3 | green4 | greenyellow | grey |
| grey0 | grey1 | grey2 | grey3 |
| grey4 | grey5 | grey6 | grey7 |
| grey8 | grey9 | grey10 | grey11 |
| grey12 | grey13 | grey14 | grey15 |
| grey16 | grey17 | grey18 | grey19 |
| grey20 | grey21 | grey22 | grey23 |
| grey24 | grey25 | grey26 | grey27 |
| grey28 | grey29 | grey30 | grey31 |
| grey32 | grey33 | grey34 | grey35 |
| grey36 | grey37 | grey38 | grey39 |
| grey40 | grey41 | grey42 | grey43 |
| grey44 | grey45 | grey46 | grey47 |
| grey48 | grey49 | grey50 | grey51 |
| grey52 | grey53 | grey54 | grey55 |
| grey56 | grey57 | grey58 | grey59 |
| grey60 | grey61 | grey62 | grey63 |
| grey64 | grey65 | grey66 | grey67 |
| grey68 | grey69 | grey70 | grey71 |
| grey72 | grey73 | grey74 | grey75 |
| grey76 | grey77 | grey78 | grey79 |
| grey80 | grey81 | grey82 | grey83 |
| grey84 | grey85 | grey86 | grey87 |
| grey88 | grey89 | grey90 | grey91 |
| grey92 | grey93 | grey94 | grey95 |
| grey96 | grey97 | grey98 | grey99 |
| grey100 | honeydew | honeydew1 | honeydew2 |
| honeydew3 | honeydew4 | hotpink | hotpink1 |
| hotpink2 | hotpink3 | hotpink4 | indianred |
| indianred1 | indianred2 | indianred3 | indianred4 |
| ivory | ivory1 | ivory2 | ivory3 |
| ivory4 | khaki | khaki1 | khaki2 |
| khaki3 | khaki4 | lavender | lavenderblush |
| lavenderblush1 | lavenderblush2 | lavenderblush3 | lavenderblush4 |
| lawngreen | lemonchiffon | lemonchiffon1 | lemonchiffon2 |
| lemonchiffon3 | lemonchiffon4 | lightblue | lightblue1 |
| lightblue2 | lightblue3 | lightblue4 | lightcoral |
| lightcyan | lightcyan1 | lightcyan2 | lightcyan3 |
| lightcyan4 | lightgoldenrod | lightgoldenrod1 | lightgoldenrod2 |
| lightgoldenrod3 | lightgoldenrod4 | lightgoldenrodyellow | lightgray |
| lightgreen | lightgrey | lightpink | lightpink1 |
| lightpink2 | lightpink3 | lightpink4 | lightsalmon |
| lightsalmon1 | lightsalmon2 | lightsalmon3 | lightsalmon4 |
| lightseagreen | lightskyblue | lightskyblue1 | lightskyblue2 |
| lightskyblue3 | lightskyblue4 | lightslateblue | lightslategray |
| lightslategrey | lightsteelblue | lightsteelblue1 | lightsteelblue2 |
| lightsteelblue3 | lightsteelblue4 | lightyellow | lightyellow1 |
| lightyellow2 | lightyellow3 | lightyellow4 | limegreen |
| linen | magenta | magenta1 | magenta2 |
| magenta3 | magenta4 | maroon | maroon1 |
| maroon2 | maroon3 | maroon4 | mediumaquamarine |
| mediumblue | mediumorchid | mediumorchid1 | mediumorchid2 |
| mediumorchid3 | mediumorchid4 | mediumpurple | mediumpurple1 |
| mediumpurple2 | mediumpurple3 | mediumpurple4 | mediumseagreen |
| mediumslateblue | mediumspringgreen | mediumturquoise | mediumvioletred |
| midnightblue | mintcream | mistyrose | mistyrose1 |
| mistyrose2 | mistyrose3 | mistyrose4 | moccasin |
| navajowhite | navajowhite1 | navajowhite2 | navajowhite3 |
| navajowhite4 | navy | navyblue | oldlace |
| olivedrab | olivedrab1 | olivedrab2 | olivedrab3 |
| olivedrab4 | orange | orange1 | orange2 |
| orange3 | orange4 | orangered | orangered1 |
| orangered2 | orangered3 | orangered4 | orchid |
| orchid1 | orchid2 | orchid3 | orchid4 |
| palegoldenrod | palegreen | palegreen1 | palegreen2 |
| palegreen3 | palegreen4 | paleturquoise | paleturquoise1 |
| paleturquoise2 | paleturquoise3 | paleturquoise4 | palevioletred |
| palevioletred1 | palevioletred2 | palevioletred3 | palevioletred4 |
| papayawhip | peachpuff | peachpuff1 | peachpuff2 |
| peachpuff3 | peachpuff4 | peru | pink |
| pink1 | pink2 | pink3 | pink4 |
| plum | plum1 | plum2 | plum3 |
| plum4 | powderblue | purple | purple1 |
| purple2 | purple3 | purple4 | red |
| red1 | red2 | red3 | red4 |
| rosybrown | rosybrown1 | rosybrown2 | rosybrown3 |
| rosybrown4 | royalblue | royalblue1 | royalblue2 |
| royalblue3 | royalblue4 | saddlebrown | salmon |
| salmon1 | salmon2 | salmon3 | salmon4 |
| sandybrown | seagreen | seagreen1 | seagreen2 |
| seagreen3 | seagreen4 | seashell | seashell1 |
| seashell2 | seashell3 | seashell4 | sienna |
| sienna1 | sienna2 | sienna3 | sienna4 |
| skyblue | skyblue1 | skyblue2 | skyblue3 |
| skyblue4 | slateblue | slateblue1 | slateblue2 |
| slateblue3 | slateblue4 | slategray | slategray1 |
| slategray2 | slategray3 | slategray4 | slategrey |
| snow | snow1 | snow2 | snow3 |
| snow4 | springgreen | springgreen1 | springgreen2 |
| springgreen3 | springgreen4 | steelblue | steelblue1 |
| steelblue2 | steelblue3 | steelblue4 | tan |
| tan1 | tan2 | tan3 | tan4 |
| thistle | thistle1 | thistle2 | thistle3 |
| thistle4 | tomato | tomato1 | tomato2 |
| tomato3 | tomato4 | turquoise | turquoise1 |
| turquoise2 | turquoise3 | turquoise4 | violet |
| violetred | violetred1 | violetred2 | violetred3 |
| violetred4 | wheat | wheat1 | wheat2 |
| wheat3 | wheat4 | whitesmoke | yellow |
| yellow1 | yellow2 | yellow3 | yellow4 |
| yellowgreen |
