The paper reviews the Hubble tension, a significant discrepancy between the predictions of the $\Lambda$CDM model and observations of the Hubble constant ($H_0$). The tension is particularly notable due to its statistical significance, ranging from 4$\sigma$ to 6$\sigma$. The review covers various experimental measurements of $H_0$, including those from the *Planck* satellite and local measurements using the distance ladder method. It discusses the possibility of a local solution and the sound horizon problem, and classifies proposed solutions into categories such as Early Dark Energy, Late Dark Energy, and modified gravity. The paper also explores the impact of systematics in *Planck* data, particularly the $A_{\text{lens}}$ anomaly, and its potential role in reducing the Hubble tension. The review concludes by discussing alternative proposals and the need for further observations to resolve the tension.The paper reviews the Hubble tension, a significant discrepancy between the predictions of the $\Lambda$CDM model and observations of the Hubble constant ($H_0$). The tension is particularly notable due to its statistical significance, ranging from 4$\sigma$ to 6$\sigma$. The review covers various experimental measurements of $H_0$, including those from the *Planck* satellite and local measurements using the distance ladder method. It discusses the possibility of a local solution and the sound horizon problem, and classifies proposed solutions into categories such as Early Dark Energy, Late Dark Energy, and modified gravity. The paper also explores the impact of systematics in *Planck* data, particularly the $A_{\text{lens}}$ anomaly, and its potential role in reducing the Hubble tension. The review concludes by discussing alternative proposals and the need for further observations to resolve the tension.