The NASB is often referred to as a “literal” translation, but a more accurate description would be “formal equivalency.”
As a simple term, “literal” has continued to be useful and to be understood in common English as something that is not interpreted, embellished, or metaphorical. When discussing Bible translations, some have attempted to define “literal” in narrower ways, but it is not a technical term.
However, “literal” translation is better referred to as “formal equivalency.” In translation a word in one language is not often “the same” as a word in another. Therefore the aim is usually to find its equivalent in the other language. For some Bible translations the goal is “functional” equivalency: basically, maintaining the form or structure of the original language has a much lower priority than conveying the contextual meaning of the passage. The NASB aims for “formal” equivalency, in which the goal is to accurately preserve both the meanings of the words of the original languages as well as their forms and sentence structure. For example, nouns that are subjects remain as such in the English, main and subordinate verbs remain as they are, and so forth. In other words, just as the NASB aims for lexical (word meaning) equivalents, it also aims for grammatical and syntactical (structural) equivalents.
The reason for this attention to detail is that meaning is subtly conveyed by the form and structure of the original languages, and that meaning can be lost when the form and structure are compromised or neglected. On occasion, something that is formally equivalent may be awkward English or misunderstood and must be modified, so the NASB “Lit” notes are provided to lend transparency to what is in the original text.
Additionally, one of the points of agreement for translation, whether the aim is formal or functional equivalency, is that most of the words in the original languages have a range of meanings, and the choice of meaning within that range depends on the context. The NASB “Lit” notes are provided with this in mind as well. They provide the actual meaning (i.e. the formal equivalent) of the word or phrase in the context of the original language.
The NASB “Or” notes, similarly, are provided due to the range of meanings that most words in the original languages possess. These notes are provided when there is some uncertainty about the best choice for the translation of a word in the context. In these cases there is a slight preference for the word in the text, but the reader can assume that the word provided by the “Or” note can legitimately be substituted, if preferred by the reader, with equal reliability as far as the original language is concerned. A special case sometimes arises of two or more Hebrew or Aramaic words spelled exactly alike (homographs). An “Or” note may refer to these cases as well, i.e. the alternative may refer to the meaning of a Hebrew or Aramaic homograph.
For a Bible to be understandable it can’t be purely literal or word-for-word; and the difference in languages requires the concept of a “word-for-word” or “literal” translation to be flexible if the Bible is also to be readable. The NASB is a formal equivalence translation that provides the reader with both an extremely accurate and readable text that is ideal for both daily reading and in-depth study.