The term "traditional art" refers to art that is made with materials that artists have used for decades, even centuries. By this I mean paint, paper, canvas, pens, pencils, etc. It is art in a traditional sense. Digital art is fairly new. It is faster and usually more cost effective (traditional art can get VERY expensive), so many professional artists today draw digitally more often. Disney has even made the switch from 2D animation, done on paper, to 3D animation, all done using computer drawing programs.
Most digital artists use drawing tablets and displays. It's still their art, line by line. When they make a mark on the tablet/display, it appears in the drawing program. There, an artist has all the colors they could ever need, and it saves a ton of time.
Traditional art is perceived as more difficult, but it all depends on the artist and their skill level. I love to draw with any medium. I've worked with graphite pencils, Prismacolor colored pencils, alcohol based markers, inks, and pastels. I've even been painting a little lately. Here are some of my most recent traditional drawings.
Do you want to learn more about the history of traditional art?