To teach English the usual basic qualifications are a degree and a TEFL certificate. There are different types of TEFL certificates as each provider (or school) issues their own.

Perhaps the most recognised TEFL certificate is the CELTA which is issued by Cambridge University. Then comes the Trinity. Then the others. As you can imagine, the CELTA is usually the most expensive (several thousand dollars). Online TEFL certificates are usually the cheapest (around 265 USD).

Will they get you the job? A CELTA is highly regarded and recognised and will be good for most jobs. For a first job at a school in, say, Asia, then almost any TEFL certificate is fine.

So to answer your question, a CELTA is a TEFL certificate.