To type an upside-down "e" on a Windows computer, type the phrase U+0259 into a Microsoft Word document, then press the x-key while holding down the Alt key. This will flip the e upside-down.
An upside-down "e" is known as a "schwa." When pronounced in English, it makes an "uh" sound as in the second syllable of the word "sofa." It produces a short sound and is usually placed in unstressed vowel positions. In English, the schwa is the most recurring vowel sound. Other examples of the schwa sound include: the "a" in "about," the "o" in "eloquent" and the "u" in supply.