# jq Lightweight command-line JSON processor for filtering, transforming, and pretty-printing JSON data. ## Pretty-Print JSON ```bash curl -s https://api.example.com/data | jq '.' ``` ## Common Filters ```bash jq '.key' # Extract a key jq '.[]' # Iterate over array jq '.[] | .name' # Extract field from each array element jq 'length' # Count array elements jq 'keys' # List object keys jq 'select(.age > 30)' # Filter by condition ```