adding content

Author: jimbogray

03-core-features/filters/included-file.md

@@ -12,3 +12,26 @@ on:
     paths:
       - 'filters/**.md'
 ```
+
+## How Path Filters Work
+
+GitHub Actions supports two path filter keys:
+
+- **`paths`** — triggers the workflow when a matching file is changed.
+- **`paths-ignore`** — skips the workflow when only matching files are changed.
+
+You can also use negation patterns to fine-tune behavior:
+
+```yaml
+on:
+  push:
+    paths:
+      - '**.md'
+      - '!**/excluded-file.txt'
+```
+
+## Notes
+
+- Glob patterns follow the same syntax as `.gitignore`.
+- At least one changed file must match for the workflow to trigger.
+- `paths` and `paths-ignore` cannot be used together in the same event trigger.