In this chapter, we learned about an unsupervised deep learning technique called AEs. We covered the definition, working principle, types, and applications of AEs. H2O, an open source library that enables us to create deep learning models, including AEs, was explored. We then discussed a credit card fraud open dataset and implemented a project with an AE to detect fraudulent credit card transactions.

Can deep neural networks help with creative tasks such as prose generation, story writing, caption generation for images, and poem writing? Not sure?! Let's explore RNNs, in the next chapter, a special type of deep neural network that enables us to accomplish creative tasks. Turn the page to explore the world of RNNs for prose generation.