In the future, computation will be human-centered. It will be freely available everywhere, like batteries and power sockets, or oxygen in the air we breathe. It will enter the human world, handling our goals and needs and helping us to do more while doing less. We will not need to carry our own devices around with us. Instead, configurable generic devices, either handheld or embedded in the environment, will bring computation to us, whenever we need it and wherever we might be. As we interact with these "anonymous" devices, they will adopt our information personalities. They will respect our desires for privacy and security.New systems will boost our productivity. They will help us automate repetitive human tasks, control a wealth of physical devices in the environment, find the information we need (when we need it, without forcing our eyes to examine thousands of search-engine hits), and enable us to work together with other people through space and time. It must be accessible anywhere. It must adapt to change, both in user requirements and in operating conditions. It must never shut down or reboot ?components may come and go in response to demand, errors, and upgrades, but Oxygen as a whole must be available all the time..