Comic books are experiencing a renaissance. It doesn't come as much of a surprise when you consider the massive box-office draws that superhero movies bring in multiple times a year. Comic books have become more mainstream in the past decade and the readership is more diverse. 2019 was the best selling year for comics in American history.  For me, what makes comic books today better than ever before is both the writing and the art. But how did we get from cheap, disposable cartoons in newspapers to a multibillion dollar publishing industry selling big, collectible books?
If you pick up a comic today, they're usually printed on a heavier, glossy paper and the printing process is almost entirely computerized. If the comic is in color, the colors are vibrant and the art is crisp. For decades, this was not the case. Until recently, comics were printed on lightweight, cheap paper. The colors were dull and the registration of the colors in the printing process isn't always properly lined up, meaning the colors bleed out of the line work in the comic. Part of these issues were due to the printing process. Most comics were printed the same way newspapers were with printing presses which kept costs down for the publisher and ultimately the consumer.
Another artifact of the printing process are “dots” which have their own interesting history going back to newsprint. Newspapers have been around for nearly as long as the printing press. A compositor - someone who puts together text for printing- would take letters from their type case and arrange them to make a form. Once all of the letters had been selected and proofread, the page or article was ready for printing and then the tray could be disassembled and the letters returned to their type case for the next project. This is known as letterpress printing and it is rarely used in large scale printing today. For centuries it was the quickest and easiest way to produce books, magazines, and newspapers, but any imagery had to be created using conventional printmaking techniques like woodcut or intaglio. The images in newspapers had to literally be cut or etched into wood blocks or metal plates and then transferred to paper with ink.
By the 19th century, journalists were able to take photographs of important events, but to reproduce these photos cheaply enough to be printed in a newspaper was a time-consuming process. Someone would need to take the image and reproduce it in either a metal plate or woodblock. Producing a gradient or even a greyscale is difficult if you're hand carving wood blocks or etching metal plates for a publication with a quick turnaround time. To help present the level of detail you see in black and white photos, certain techniques were created to produce a wide range of greys for papers that were printed only with black ink.
For centuries artists have known that if you create a lot of small marks on a surface you can create the illusion of shading even if your medium produces a consistent solid color like ink does. This is known as stippling. Similarly, overlapping colors can create new ones which is really helpful to avoid mixing inks together to create a full palette. Instead, only four colors can be used: cyan, magenta, yellow, and black (usually referred to as “key” in printmaking) to create a full spectrum of color by using a variety of different overlapping techniques. Take a look at the ink cartridges in a modern day inkjet printer and you'll see these colors - CMYK - are still used today.
This is where Ben Day dots come in to give these newsprint images colors and tonality. Ben Day dots, named after their creator Benjamin Henry Day Jr., are a means of producing a wide variety of colors using four colors of ink. Also, because they don't apply solid fields of color to a page, they technically save money in terms of the amount of ink that needs to be applied to a page. From the creation of the technique in the 1870s up to the middle of the 20th century, they were a common option for printing full color comics and images. Eventually Ben Day dots were phased out in favor of halftone printing which also leaves behind a characteristic dot pattern if you look closely at a printed page.
Ben Day dots aren't used anymore for printing in general (unless it's an intentional effect), but they're still associated with comic books much like panels, speech bubbles, and written sound effects. The way comics & advertising were printed was apparent to artists of the Pop Art movement in the 1950s and 60s like Roy Lichtenstein who is most famous for recreating panels of comic books as large, painted canvases. Lichtenstein keyed in on the dot artifacts of the printing process and exaggerated them for artistic effect in his artwork. His work was and still is controversial. At the time it was primarily because comics were not regarded as art and Lichtenstein lifted images from comics without giving any credit to the original artists.
These printing processes also limited artists on their color palettes. Marvel Comics, for example, is considered to have only used 64 colors into the 1980s because that’s how many ways red, blue, and yellow can be combined using quarter-step tints. These tints were applied in printing using Ben Day dots, halftone screens, and the like. In practice though, most comics wouldn’t come close to this variety of colors to save on ink. If you want to emulate the look of golden or silver age comics, this is a handy palette to use.
Today, the artwork found in comics is incredibly varied and artists are only limited by the size of the page and not the constraints of a printing process. Artists have used every medium under the sun including watercolors, sprites, and photography to illustrate their comics. However many full-color comics are now illustrated digitally and printed with a much broader palette. With the advent of the graphic novel, comic artists have more freedom as they're not necessarily bound to a monthly issue format and can spend more time on their creations.
When we hear “comic art” we tend to think of characters dressed in bright primary colors and drawn with thick, black outlines that exist within a series of squares. But that is the convention and there are many comics in print today that are far from conventional.