This thesis examines meaning-making in three different areas of undergraduate physics: the refraction of light; electric circuits; and, electric potential and electric potential energy. In order to do this, a social semiotic perspective was constituted for the thesis to facilitate the analysis of meaning-making in terms of the semiotic resources that are typically used in the teaching and learning of physics. These semiotic resources include, for example, spoken and written language, diagrams, graphs, mathematical equations, gestures, simulations, laboratory equipment and working practices. The empirical context of the thesis is introductory undergraduate physics where interactive engagement was part of the educational setting. This setting presents a rich data source, which is made up of video- and audio recordings and field notes for examining how semiotic resources affect physics teaching and learning. Theory building is an integral part of the analysis in the thesis, which led to the constitution of a new analytical tool – patterns of disciplinary-relevant aspects. Part of this process then resulted in the development of a new construct, disciplinary affordance, which for a discipline such as physics, refers to the inherent potential of a semiotic resource to provide access to disciplinary knowledge. These two aspects, in turn, led to an exploration of new empirical and theoretical links to the Variation Theory of Learning. The implications of this work for the teaching and learning of physics means that new focus is brought to the physics content (object of learning), the semiotic resources that are used to deal with that content, and how the semiotic resources are used to create patterns of variation within and across the disciplinary-relevant aspects. As such, the thesis provides physics teachers with new and powerful ways to analyze the semiotic resources that get used in efforts to optimize the teaching and learning of physics.