Fonts without the extra little tags on the letters are called "sans serifs," which literally means, "without wings." Some of the earliest sans serif fonts were cut in Italy in the early 1500s. They were popular with printers because the lack of extra bits on the ends of the letters allowed them to print more letters per line than the blockier and more complicated serifs.
The printers in Germany, not wanting to lose their market for the established serif fonts, made a lot of noise about the sans serif fonts being less readable and somehow inferior to the serifed Romans. The propaganda from that campaign was very effective, for even today san serif fonts are considered "less readable." Research into the readability of various fonts has found no significant difference between serif and sans serif fonts for the majority of printing uses. One exception is the use on computer monitors where studies have found sans serif fonts to be MORE readable, especially in the smaller sizes.
There are two classes of sans serif in use today: Geometric and Humanist.
