Twitter introduced its new version of the API, V1.1, this changes the whole authentication process. According to a Wired article, Twitter’s New API Rules Likely Spell the End of Third-Party Clients, developers saw this as a threat to data usage. Anyone using Twitter now has to be authenticated and has a rate limit. There is no more typing the search into the URL bar.
How to create an application in the twitter developer page:
2) Click create new application
3) Fill out the application details page
4) Under the OAuth tool tab you can access your consumer key, consumer secret, access token, and access token secret for authentication.