Does knowledge still have value in current era of large-scale pretraining? In this tutorial, we will comprehensively review existing paradigms for multimedia knowledge discovery and encoding, and focus on their contributions to vision-language pretraining. We categorize the knowledge into internal self-knowledge and external knowledge. Internal knowledge are extracted from text and vision modalities, such as structured entities, relations, events, and event procedures. We will focus on the structural aspects of the knowledge and address two key challenges regarding the acquisition of knowledge and encoding of structure across multiple modalities. External knowledge can be obtained from knowledge bases or language models, and we will exemplify their use to assist in commonsense understanding of vision modalities, with a focus on the temporal and cognitive aspects. The objective of this tutorial is to introduce participants to recent trends and emerging challenges in knowledge-driven vision-language research, as well as learning resources and tools for participants to obtain ready-to-use models, prompting thorough discussions regarding the impact of structured knowledge on text and vision learning.