Sometimes it' spelled "chilli" in the UK and "chile" in the Southwestern US, including with reference to the derived products.
Hot, red chilies are a staple in Vietnamese marinades and other dishes. These include the tiny, exceptionally hot bird's-eye chilies.
Use whole dried chilies after removing the seeds or use dried flakes.
Chili pepper pods, which are berries, are used fresh or dried. Chilies are dried to preserve them for long periods of time or may also be done by pickling. Dried chilies are often ground into powders, although many Mexican dishes including variations on chiles rellenos use the entire chili.