About by vs ’bye vs buy
These are probably confused with each other more often through hastethan through actual ignorance, but “by” is the common preposition inphrases like “you should know by now.” It can also serve a numberof other functions, but the main point here is not to confuse “by” withthe other two spellings: “’bye” is an abbreviated form of “goodbye”(preferably with an apostrophe before it to indicate the missingsyllable), and “buy” is the verb meaning “purchase.” “Buy” can also be anoun, as in “that was a great buy.” The term for the position of a competitor who advances to the next level of a tournament without playing is a “bye.” All others are “by.”
Source: http://www.wsu.edu/
