Cargo is Rust's package and dependency manager, and it is similar to Bundler, npm, pub, or pip for other languages. Although you can write Rust programs without it, Cargo is nearly indispensable for any large project; it works the same whether you work on a Windows, Linux, or a Mac OS X system. The installation procedure from the previous section includes the Cargo tool, so Rust is shipped with tooling included.
Cargo does the following things for you:
cargo test ...