The speech of the Sephardic Jews have been defined as both language and dialect, depending always on the standpoint of the analyzer, but is it a language on its own right or is it “just a dialect”? What is, then, the difference between both concepts? In the case Judeo-Spanish could be considered a language, what are the criteria taken into account in the classification? In an attempt to answer these questions I will provide facts on the origin of both terms, their modern and politicized use as well as on the historical vicissitudes of Judeo-Spanish and its speakers. Their literature, both laic and religious, is covered with an emphasis on the most researched and relevant genres, namely: the biblical Sephardic translations, the Romancero and the modern press of the 19th Century. A descriptive presentation of Judeo-Spanish main grammatical features precedes the last chapter, where both the diagnosis of Judeo-Spanish in the 20th Century, and its prognosis for the 21st, are given with the aim of determine its present state.