C1 (Level) refers to an advanced proficiency level in the Common European Framework of Reference for Languages (CEFR). At this level, learners can understand a wide range of demanding texts and express themselves fluently and spontaneously without much obvious searching for expressions. They can also produce clear, well-structured text on complex subjects. Individuals at the C1 level can effectively use language in social, academic, and professional contexts. They can engage in discussions, present arguments, and understand implicit meanings in conversations. This level indicates a high degree of language competence, allowing for nuanced communication.