Back in the 15th century, the first book was printed on the first ever printing press. Small blocks of letters were placed together, brushed with ink then stamped on the parchment. Since then, the technology has changed drastically. The concepts are similar, but the speed and equipment look nothing alike.
Unlike in the Middle Ages, the modern printing press offers multiple types of printing. Offset, relief and gravure all use a printing plate to transfer ink to the material but operate differently. Offset printing uses a roller to transfer images from the inked plate to the printing material. Relief printing is the most popular and harks back to the original press with the reverse material put on a plate, inked then pressed onto the material. Gravure involves digging out the plate versus raising it to create the material, inking then pressing onto the material. Many of these presses use doctor blades for flexo printing to prevent the ink clogging up the machine. There are other types of printing but not as commonly used.
Printing is available in full color, black and white or grayscale. Full color requires the use of four distinct colors to produce the color spectrum: black, cyan, yellow and magenta. Black and white printing only uses black ink making it a cheaper alternative to color. Grayscale helps create images because of the optical illusion created by using dots of black in a variety of sizes to create a picture. The type of color scheme you use depends on your budget, application and needs.
Printing presses may no longer look much like they did when Johannes Gutenberg created movable type in 1450, but they follow similar principles to deliver sharp or contrasted images and words. A variety of material can be printed on from clothing to paper to vinyl.