Language

A language is a system of signs that allows for their transmission and in particular for the transmission of the meaning they carry, making languages essential for communication.

As important as this potential to understanding language, it is also important to understand its boundary. A language can't represent all things, not only because not all things have an appropriate representation of it (such as words, expressions, descriptions) but because they may simply be ineffable, novel or too complex.

For example, the mind's experience is overly complex and even our own memory only stores it partially, temporarily and possibly with mistakes. You can describe in extensive detail something as mundane as a tedious day at work, but you can't impart to your listener the full breadth of this experience, every detail in the sights, sounds, and in particular the feelings you have felt during the day.

This does not hinge on the sharpness of your or your listener's mind nor your or their proficiency in the language you are speaking. There simply is no transliteration possible from that fully subjective experience to words, not to mention the most intense and unique of experiences.