Semiotics is the study of signs and sign-using behavior. Computational semiotics is an interdisciplinary field which proposes a new kind of approach to intelligent systems, where an explicit account for the notion of sign is prominent. Our fundamental thesis is that information concentration processes appear in successive layers of deep learning models: each layer aggregates information from the previous layer of the network. In computational semiotics, this information concentration is known as superization, and it is accompanied by a decrease of entropy: signs are aggregated into supersign. Our interdisciplinary approach enables us to depict superization processes within deep learning models. This is a novel semantic interpretation of deep learning. We use concepts from computational semiotics to explain decision processes in deep learning. Semiotic tools can be used to optimize the architecture of deep neural networks. Interpretability/explainability and architecture optimization of neural models are currently among the hottest topics in machine learning. We illustrate our semiotic approach with several applications. Our contribution can be seen as the initial move in establishing a cohesive semiotic framework for deep learning models.