This article reviews common artefacts in cone beam CT (CBCT) and discusses their causes and effects. Artefacts in CBCT arise due to discrepancies between the mathematical models used for reconstruction and the actual physical imaging process. These artefacts can interfere with the diagnostic process, making it essential for users to be aware of them. The article outlines the basic 3D reconstruction concept used by CBCT scanners, which involves backprojection of X-ray projections. The Feldkamp algorithm is commonly used for this process, but it has limitations, such as degradation with increasing cone angles. Artefacts can be caused by various factors, including beam hardening, partial volume effects, aliasing, ring artefacts, motion artefacts, noise, and scatter. Each of these artefacts is discussed in detail, with examples of their appearance and impact on image quality. The article highlights the importance of understanding these artefacts to improve diagnostic accuracy and mentions ongoing efforts to develop techniques for artefact reduction. It concludes that while CBCT has advantages, it also introduces specific artefacts that require attention and advanced reconstruction methods to mitigate.This article reviews common artefacts in cone beam CT (CBCT) and discusses their causes and effects. Artefacts in CBCT arise due to discrepancies between the mathematical models used for reconstruction and the actual physical imaging process. These artefacts can interfere with the diagnostic process, making it essential for users to be aware of them. The article outlines the basic 3D reconstruction concept used by CBCT scanners, which involves backprojection of X-ray projections. The Feldkamp algorithm is commonly used for this process, but it has limitations, such as degradation with increasing cone angles. Artefacts can be caused by various factors, including beam hardening, partial volume effects, aliasing, ring artefacts, motion artefacts, noise, and scatter. Each of these artefacts is discussed in detail, with examples of their appearance and impact on image quality. The article highlights the importance of understanding these artefacts to improve diagnostic accuracy and mentions ongoing efforts to develop techniques for artefact reduction. It concludes that while CBCT has advantages, it also introduces specific artefacts that require attention and advanced reconstruction methods to mitigate.