Students in the past have asked about appropriate attribution of images you might be using in the TwitterBot assignment.

You can't throw quotation marks around a photograph, and often providing full citation within a tweet is impractical and unnecessary. I am not too concerned with these issues for memes, pop-culture parodies, things like that — here are some student projects from past years that may test these image usage lines a little bit in different ways but seemed ok to me for the purposes of this project:

...But it's still important (in some cases) to show respect to the creators of materials you use! For the purposes of a Twitter bot, I think the most important thing is to consider the ethical questions, both with respect to the bot's possible effects on the source of the image, and possible effects on the bot's audience. For example: Let's say your bot is posting beautiful paintings, and construct some extreme examples:

If you post the Mona Lisa, you don't need to worry about hurting da Vinci, and it's also reasonable to assume the bot's audience would know it isn't your original painting either, especially if the bot is called "Great Renaissance Painting Bot" or whatever.
If you're posting art by some obscure teenager living somewhere, that person might be hurt by having their artwork taken without permission (or at MINIMUM attribution), and depending on how your bot is presented, the audience could be misled too, e.g., if the bot was called "Hemi Joranson, Art Student" or something, right?

One option for attribution might be to create and link out to a little bibliography somewhere — an itty bitty site, for example, might be a good way to do this (you'd probably want a link shortener, e.g., https://bitly.com/)

Later, for the slideshow assignment, we will consider more stringent standards, e.g., even for creative commons images, there are quite detailed recommendations for how best to attribute images: https://wiki.creativecommons.org/wiki/Best_practices_for_attribution

Hope that helps!!