Modern language refers to any dialect that still is used as a means of human communication. In the United States, as a whole, the modern language most taught and used still is English. In some border counties with Mexico, Spanish is the predominant modern language. So-called "dead" languages like Latin or Sanskrit, by contrast, may be taught in some circles as classical languages, but that does not make them modern.
Depending on the country and even the region of that country, different modern languages may be the first taught to children. Others, like English or French, are common secondary acquired languages. All are considered modern languages, as long as communities of people somewhere on Earth are using them. Trends vary by country. In India, for instance, two languages are commonly spoken — the Hindi spoken at home and the English used at work or school. In many non-English-speaking countries, English is by far the most commonly taught second language.
Public schools in the United States offer a handful of secondary modern languages for students to acquire more than one useful language. Common to this group are Spanish, French, German or even Chinese. Many schools, particularly college preparatory programs, also offer Latin or classical Greek to illustrate many of the common roots found in modern western languages.
Universities are the chief repository and perpetuating force of all modern languages, aside from the native countries that use them most. American liberal-arts colleges typically offer instruction on a wide range of modern languages. These vary from Mandarin Chinese, Spanish, French and Arabic to even more underutilized tongues like Welsh or Sri Lankan Sinhalese. World relations or international business students often attempt to achieve absolute fluency in one or more extra languages to improve their chances for success upon graduation and to hone more closely into a few chosen cultures.
Within the United States, Spanish is the most predominant language taught as a second language at the university level. A decade ago, Arabic was one of the least popular, in 10th place, according to the Association of Departments of Foreign Languages. Today, perhaps due to more persistent conflict and involvement in the Middle East, Arabic and its dialects have enjoyed a healthy American renaissance.
The Modern Language Association maintains a detailed, interactive map of the United States that shows, county-by-county, which languages are spoken by what percentage of the population. English predominates the nation, of course. A cursory examination, however, of dozens of counties along the U.S. border with Mexico reveals that Spanish has slowly become, if not the official modern language, at least the true modern language of the locals.