Feb 4, 2011 ... Writers sometimes use the surname of the first author followed by et al. at the first mention of a work that has three, four, or five authors. Only when a work has six or more authors should the first in-text citation consist of the first author followed by et al. With five or fewer authors, all the author surnames ...
Jun 21, 2011 ... Et al. does not need to be italicized in normal use. It does take a period after the second word, even when it falls in the middle of a sentence. In general, et al. is best reserved for citations and other parenthetical remarks in academic or other types of formal writing. It can sound unnatural when read aloud, ...
It is important to use these abbreviations literally and to punctuate them correctly. Many writers confuse "e.g." and "i.e.," and many type "et al." improperly or do not properly recognize what words it represents. The abbreviation "e.g." is from the Latin exempli gratia and means, literally, "for example." Periods come after each ...
I would say there is a definite distinction between the two, in definition and in proper usage. Et cetera, often shortened to etc., means literally 'and the rest'. Et alii, often shortened to et al., means 'and others' and can be thought of as a specific case of et cetera when the 'rest' refers to a list of persons.
Even if you don't speak Latin, you should know the two meanings of et al. Learn what et al. is, how to use it, and what mistakes to avoid.