Which technology allows applications to run consistently across different environments?

Applications need to operate seamlessly across different environments, whether they are being deployed on a developer's laptop, a testing server, or in a production cloud environment. Containers are a technology that allows for this consistency by encapsulating an application and its dependencies together in a single package. This ensures that the application will run the same way regardless of where it is executed.

Containers leverage lightweight virtualization to isolate applications from each other and from the host system. By packaging everything the application needs to run (such as libraries, configuration files, and binaries), containers eliminate issues related to environmental discrepancies, such as differences in operating systems or software versions. This portability is a pivotal characteristic of containers that makes them particularly effective in modern cloud-native development practices.

Unlike traditional virtual machines, which require a full operating system to run each application, containers share the host's operating system kernel, making them more efficient and quicker to start. On the other hand, data centers and cloud brokers do not inherently provide the consistency in application behavior across environments, as they are focused more on infrastructure management and resource allocation rather than application portability.