This character's written form began with the drawing of a horse standing, its mane and tail clearly depicted. A few hundred years later, the character's written form developed into scripts we use today: 馬 (traditional form) and 马 (simplified form). The flowing mane, tail and the four legs are still part of the current character's form.
In Chinese culture, 马 is respected for its hardworking spirit and is an important motif in Chinese mythology. 马 is often referenced in Chinese culture (2014 is the year of the 马) and literature (Lu You's poem "Rainstorm on Nov. 4th") and featured in many Chinese paintings (Xu Beihong's "Galloping Horse").
马 is also a radical and is used to form many different Chinese characters: 驰 (gallop)，驮(pack)，驻 (resident).