<p>Numerous industries have undergone significant transformation since the advent of 3D printing technology in the 1980s. In 2013, the integration of time with the spatial dimensions of 3D printing prompted the emergence of 4D printing. It preserves the fundamental characteristics of 3D printing, including minimizing material waste and obviating the necessity for moulds, dies, and machining. 4D printing allows for the development of programmable material, which can alter shape, features, and function over time. However, the discovery of novel materials with programmable features that are also stimuli-responsive has not been properly reviewed. This review provides an in-depth analysis of contemporary 3D printing materials that enable 4D printing, with a particular focus on novel "smart materials" that exhibit predictable, stimuli-responsive behaviour. In addition, the review explores the software tools essential for achieving efficient 4D printing results, existing and emerging 4D printing techniques, recent advancements in printing methodologies, and the latest innovations in the field. A key novel aspect of this review is its thorough examination of the current limitations of 4D printing technologies, highlighting critical research gaps that require urgent attention to fully realize the potential of this transformative technology.</p>