The Purdue APA Style Guide covers all the conventions included in the latest edition of the APA Style Manual.
This resource is great for learning how to cite tweets, videos, and other electronic forms of media. It is common to make use of tweets in syntax and sociolinguistics, so make sure your citations are correct.
This is the official online resource for the Chicago Manual of Style. Any and all questions you have about Chicago style will be answered here.
The Purdue Chicago Style Guide covers all the conventions included in the latest edition of the Chicago Style Manual. People who are familiar with Purdue's APA Style Guide may prefer this resource.