This document defines key terms related to English language learners (ELLs). It explains that an ELL is a student whose native language is not English and who is acquiring English. Several programs for educating ELLs are described, including bilingual education, immersion, sheltered English, and different types of bilingual and English as a second language programs. The goals and characteristics of dual language education, developmental bilingual education, transitional bilingual education, structured immersion, ESL pullout, and immersion programs are summarized.