Helm Chart
In plain terms
A packaged, templated set of Kubernetes resources.
Going deeper
A Helm chart bundles Kubernetes manifests with configurable values so apps can be installed and versioned like packages. It simplifies deploying complex apps.
Under the hood
Templating and values enable reuse across environments; Helm is the de facto Kubernetes package manager.
Examples
Installing apps on K8s, parameterized deploys, app packaging, releases.
Think of it like...
Like an app-store installer that sets up a whole application with chosen settings.