Yarn¶

Yarn is a package manager for Node.js. It keeps track of the exact versions of each dependency in your project. This ensures that all developers working on the project use the same versions of dependencies, which makes your project more consistent and predictable.

Yarn vs Npm¶

Yarn and npm are both package managers for JavaScript, but they have some differences that might make you prefer one over the other:

• Performance: Yarn is generally faster than npm because it installs all packages concurrently (at the same time), while npm installs one at a time.
• Yarn.lock: Yarn generates a yarn.lock file which ensures that the exact same version of a dependency is installed across all environments. npm also has this feature (package-lock.json), but it was introduced in npm 5, so Yarn had the advantage first.
• Workspaces: Yarn has a feature called "workspaces" that allows you to manage multiple packages within a single parent directory. This is particularly useful in a monorepo setup.
• Offline Mode: Yarn can install packages from a cache on your computer, allowing you to install packages without an internet connection if you've installed them before.
• Interactive Upgrade: Yarn provides an interactive upgrade mechanism which helps you to manage your dependencies.

Both Yarn and npm are good choices, and both are widely used in the JavaScript community. The choice between them often comes down to personal preference or specific needs of the project.