[qiqing]

Not a Japanese speaker, but I'm a native Chinese speaker. I know that Bingfa (The Art of War) could also be translated as The Practice of War or Methods of War. Translations are always interpretations because phrases aren't exact.

The Art of JavaScript sure does sound more exotic than The Practice of JavaScript, so I can see why a translator would make that choice.

[SamBam]

Even in English, one of the meanings of "art" is a "skill as a result of learning or practice."

The word itself comes from Latin "ars," meaning a skill, a craft.