Stack Overflow API
Stack Overflow (stackoverflow.com) has 2 public methods: search questions and get answer. Each costs 1 credit per completed run (1¢ with pay as you go); failed runs are free.
Unofficial. Not affiliated with or endorsed by Stack Overflow.
Methods
2Finds Stack Overflow programming questions matching plain-language search words, optionally filtered by tag and answer status, with a chosen sort order.
Returns title, score, answer count, accepted-answer flag, tags, asked date, views, link, question number
Readstackoverflow.com/search_questionsGets a Stack Overflow question and its best answers, from a question link or a plain-word search. A search picks the most relevant answered question. The accepted answer comes first, then answers by score.
Returns question title, text, link, tags, answers (text, score, accepted, author, date, link)
Readstackoverflow.com/get_answer