_The following are key concepts for Hugo site customization. Hugo permits you to **supplement or override** any theme template or static file, with files in your working directory._
For including a different file than what the theme ships with. For example, if you would like to use a more recent version of jQuery than what the theme happens to include, simply place an identically-named file in the same relative location but in your working directory.
Anytime Hugo looks for a matching template, it will first check the working directory before looking in the theme directory. If you would like to modify a template, simply create that template in your local `layouts` directory.
In the [template documentation](/templates/overview/) _each different template type explains the rules it uses to determine which template to use_. Read and understand these rules carefully.
This is especially helpful when the theme creator used [partial templates](/templates/partials/). These partial templates are perfect for easy injection into the theme with minimal maintenance to ensure future compatibility.
**Warning**: This only works for templates that Hugo "knows about" (that follow its convention for folder structure and naming). If the theme imports template files in a creatively-named directory, Hugo won’t know to look for the local `/layouts` first.
If the archetype that ships with the theme for a given content type (or all content types) doesn’t fit with how you are using the theme, feel free to copy it to your `/archetypes` directory and make modifications as you see fit.
**Default** is a very powerful force in Hugo, especially as it pertains to overwriting theme files. If a default is located in the local archetype directory or `/layouts/_default/` directory, it will be used instead of any of the similar files in the theme.
