Language is the usage of instrumented sounds, gestures, or symbols to communicate meaningful expressions. It is also the usage of innate systems of symbolic meaning, such as in the case of how the brain tells the arm or leg to move, or how human beings use cognitive objects in logical ways to think.
By first inference, the idea of language is bound to the idea of making sounds, because of the human ability to make sounds as the primary medium for language, this faculty simply called "speech." The ability make repetitious and systematic usage of sounds to make statements of various forms is called "language faculty," and the idea of determining language faculty in people (and also in other creatures) is a core idea in society (discerning intellect) and to a certain extent in science (cognitive science).
Whether in spoken form or not, the granular element of a language is called a "word," which are ideas in the mind which, in the spoken form, have a sound or combination of sounds bound to them, and for other forms, such as writing, have an associated string of letters or "glyphs." For words to be usable they first have to be defined and standardized, which is to say communicated among a learning group.
Understanding language starts with an idea first of what language is, and the common naive answer: language is the usage of words to make meaningful expressions, is near sufficient for one half of the idea of language. The other half, is that language and vocabularies have changed over time, and with changes in the way that people have lived.
Phonology, or sound systems
In learning another language, one deals first with the idea of hearing speech in that other language with some kind of sense of where words begin and end. The study of sounds and how sounds are practiced and learned in the brain is called "phonology."
The idea with the usage of sound is that there are only so many sounds humans can make, and so that limited spectrum of sounds is used in an assigned way to words.
The idea behind the modern languages is in the democratic model, to use the easiest sounds there are to make, and then lose the phonological elements (phonemes, or just sounds) which are older form and difficult. In the Common English, the short single syllable sounds are reserved for operation words and other basic and functional uses.
To understand African languages, its important to know that the unusual clicking and trill sounds are there because they predate the usage of sonorous vowel and consonant sounds that we have today.
To understand Asian languages, its important to know that the tonal aspect of these languages comes about in part due to the writing systems being ideographic, and the phenomenon of binding between one glyph to one syllable means that syllables are flexed in a tonal way.
To understand European languages, its important to know that the alphabetical writing system sufficiently preserves the vowel flexation principle, leaving consonants very much the same over time, and that unusual tones are due to bindings enforced in the alphabet. In addition to being easier and more democratic for learning (as evident in the name "w:demotic"), the European writing systems allow facile vocabulary development.
To understand Native languages (mainlander and islander), its important to know that they have great language differentiation due to typically lacking a writing system, and thus the principles for fortifying these languages over time deal with forming large vocabularies of single and double syllable words.