CMYK is the color model used for printing. It stands for Cyan, Magenta, Yellow and Key (the printing term for black), the four inks a press layers onto paper to build up a full-color image. Each ink absorbs part of the light hitting the page, and what bounces back to your eye is the color you see.
Think of mixing paint. Start with a white page and add ink, and it gets darker; pile on all four and you get close to black. That is the opposite of a screen, where you start with black and add light to get brighter. This is why a flyer and a website using the “same” red can look slightly different, and why designers care about color models when work moves between print and screen. A red defined as a hex code for the web is not automatically the right CMYK recipe for a printer.
The catch is range. Screens can show neon-bright colors that ink simply cannot match, so a vivid design often looks calmer once it is converted for print. Good practice is to design in the model that matches the final output and to check a proof before a big run. A printer can also tune the ink mix, and a quick test sheet costs far less than reprinting ten thousand brochures. CMYK has a few quirks worth knowing. Black built from cyan, magenta and yellow alone looks muddy, so presses add a dedicated black, the K in the name. Solid blocks of dark color often use a richer mix to look deep instead of grey. And the same file can shift between two printers, because paper, ink and calibration all play a part. That is why a colour proof matters.
At TopDevs we keep client brand colors defined in both CMYK and RGB so a logo looks consistent whether it lands on a business card or a landing page.
