When studying the Web, one can’t help but notice how massively scalable it is. There are hundreds of thousands of websites and billions of requests per day traveling across it. Terabytes of data are downloaded from the Internet every hour. Websites like Amazon and Bank of America process millions of transactions per day. In this chapter, I’ll discuss some features of the Web, specifically within HTTP, that make it more scalable and how you can take advantage of these features within JAX-RS applications.