The target audience was English language learners and ESL teachers.
Recent research by Billuroğlu and Neufeld (2005) confirmed that the General Service List was in need of minor revision, but the headwords in the list still provide approximately 80% text coverage in written English.
The research showed that the GSL contains a small number of archaic terms, such as shilling, while excluding words that have gained currency since the first half of the twentieth century, such as plastic, television, battery, okay, victim, and drug.
The GSL is not a list based solely on frequency, but includes groups of words on a semantic basis.
[4] There are two major updates of the GSL: Some ESL dictionaries use the General Service List as their controlled defining vocabulary.