--- date: created: 2025-07-01T17:30:00Z categories: - Explainers authors: - fria tags: - Privacy Enhancing Technologies - Differential Privacy license: BY-SA schema_type: BackgroundNewsArticle description: | Privacy Pass is a new way to privately authenticate with a service. Let's look at how it could change the way we use services. --- # Privacy-Enhancing Technologies Series: Differential Privacy Is it possible to collect data from a large group of people but protect each individual's privacy? In this entry of my series on privacy-enhancing technologies, we'll discuss differential privacy and how it can do just that. ## Problem It's useful to collect data from a large group of people. You can see trends in a population. But it requires a lot of individual people to give up personally identifiable information. Even things that seem inocuous like your gender can help identify you. 87% of Americans can be identified by three pieces of information: ## History Most of the concepts I write about seem to come from the 70's and 80's, but differential privacy is a relatively new concept. It was first introduced in a paper from 2006 called [*Calibrating Noise to Sensitivity in Private Data Analysis*](https://desfontain.es/PDFs/PhD/CalibratingNoiseToSensitivityInPrivateDataAnalysis.pdf)