Source: Quickie Poll, Creative Commons: http://beautyeditoroncall.com/2011/08/25/quickie-poll-which-makeup-technique-is-the-trickiest/
A sample that is not carefully thought out to limit biases; the resulting sample will likely not accurately represent the population at large.
A poll that is hastily prepared without care for randomness or reduction of biases. The goal is to get the largest amount of responses in the shortest amount of time.
A sample that obtains its participants through the easiest means possible.