As typography is often associated with the style and appearance of printed text and handwriting, as well as the art of manipulating them for visual appeal, I consider this design practice to be important for many reasons. First and foremost, typography allows us to implement ideas that are unique to letters when contrasted to art forms affecting elements outside of type and writing. For example, when emphasizing mood and tone, manipulating the appearance and size of a word can evoke a more direct meaning to a viewer in a way that is verbally different from what can be seen in art relying on just visual elements such as paintings, illustrations, and photos without captions.
Second, typography is important due to its contributions toward the historical use of fonts. Fonts provide an almost endless interpretation of how typed text can look like and due to the many styles of fonts (or typefaces) available, their use have encompassed many mediums ranging from book titles and common signage to special documents and extravagant marquees representing many genres. Like with the previous example, the appearance of text can evoke feelings, or in this case contribute to a thematic style of work expressed through a specific typeface such as semi-formal (Calibri type) and antiquated (Gothic type) as two examples.
As aforementioned, there are two major reasons why typography is important and given the scope of how fonts and typefaces are implemented, it is a branch of graphic design that still holds a lot of creative value today as there are even careers are based on this sub-discipline.