ESL - English as a second or foreign language is the use of English by speakers with different native languages. (Английский, как второй язык для говорящих на разных своих языках)
UFO - НЛО (Unknown Flying Object)
UFO - are an English rock band that was formed in London in 1969.
They became a transitional group between early hard rock and heavy metal and the new wave of British heavy metal.
Eta (Η, η) - is the seventh letter of the Greek alphabet.
ETA - Estimated time of arrival — ожидаемое время прибытия.
ETA Systems - компания по производству суперкомпьютеров.