Jalapeño

The jalapeño is a small to medium-sized chile pepper that is prized for the hot, burning sensation that it produces in the mouth when consumed. In comparison with other chiles, it has a heat content that varies from mild to hot, depending on how it was grown, and how it was prepared. Most sources agree that much of the heat, due to capsaicin and related compounds, is concentrated in the seeds and the veins - deseeding and deveining can reduce the heat imparted to a recipe that includes jalapeños.

A chipotle is a jalapeño that has been smoked.

Most chile peppers are of species Capsicum annuum, as is the jalapeño. The links for chile peppers and capsaicin above provide considerable information that jalapeños have in common with other chile peppers.