Originally Posted by canadiancow

If it's being booked on AC, the options are:
Basic (what you expect)
Standard (formerly Tango, reduced mileage earning, no free seat selection, etc.)
Flex ("regular" economy)
Comfort (unsure if it's offered on international, but some benefits like preferred seats, etc.)
Latitude (full Y/B)

Be mindful of which brand you buy, as they all have different perks.