There is western red cedar roofing, there is white cedar roofing, there is Alaskan yellow cypress roofing which is also referred to as Alaskan yellow cedar roofing. Alaskan yellow cypress roofing, the best by far, is more expensive than the red cedar and the white cedar.
Summing up: 1  An abbreviation is a shortening of a word or a phrase. 2  An acronym is an abbreviation that forms a word. 3  An initialism is an abbreviation that uses the first letter of each word in the phrase (thus, some but not all initialisms are acronyms).
Acronym is a fairly recent word, dating from the 1940s, although acronyms existed long before we gave them that name. The term was preceded in English by the word initialism, meaning an abbreviation formed from the initial letters of a phrase, and which has been in use since the late 19th century.