BlankSlate WordPress Theme
A naked WordPress theme, powering over 10k websites.
You can use BlankSlate however you like, but here are some common options...
I care about theme updates.
Use a child theme.
It's extremely important that if you want to receive the latest updates without breaking your website, that you NOT edit the theme files directly. If you do, they'll be overwritten every time you update. Download child theme. Learn more about child theming.
Use only CSS.
Technically, if you don't want to use a child theme, but still want the latest updates, you could stick to only styling your website via Appearance > Customize > Additional CSS or some other plugin or means of adding custom CSS.
I don't care about theme updates.
Build a custom theme.
Whether for your own projects, client projects, or even a custom theme you intend on submitting to WordPress.org, hack up the files of BlankSlate directly as much as you please. Just make sure to replace all occurrences of "blankslate" with your own project or theme name. Learn more about theming.
Customize BlankSlate as-is.
If you don't care about updates and have no big ambitions for building custom themes, you can just jump in and hack it up. However, at the very least, I HIGHLY recommend changing the version number to "9999." That way, you won't get update nags and if anyone else ever comes onto the project later, they won't accidentally update the theme and destroy all the customizations (I've seen it happen plenty of times)!