Decades of research have established that most English Language Teaching (ELT) contexts rely on textbooks and corresponding materials to drive the education process. Textbook analysis as a vital quality control check of these products has also become a popular trend in applied linguistics and "second language" (L2) research. In the main, ELT textbooks have been conceptualized in past literature as supporting target language proficiency attainment while also giving the teacher everything required to conduct a lesson. Textbook analysis has subsequently checked products' utility and quality in relation to such proficiency development. Over time, the scope of textbook analyses has expanded to include issues such as cultural representations in these products to address how the products help students become better at English in a multicultural and globalized world. While teachers and researchers can reference numerous well-known books on these phenomena, a concise summary of how textbooks function within ELT contexts and the defining features of textbook analysis research appears to be lacking. This brief report meets this need and is useful to stakeholders in the ELT community, such as teachers and program managers, who might not have the time nor the resources to consult such extensive sources of information.