Normal and italic ampersands in Adobe Garamond Pro
Throughout historic documents you will frequently find &c. written to represent etcetera or etc. — a latin expression meaning and other things. This is because the ampersand is the ligature for et. A ligature is a typographic term for when two characters are combined into a single glyph.
Today the et roots of the ampersand can still be seen in the italic form of many typefaces. The figure to the right is an example of the normal and italic ampersand in Adobe Garamond Pro. Looking at the italicized form you will see the e and t that it is composed of.
Since et is latin for and that is also why the ampersand is commonly used in place of and.