This review provides an updated overview of Alzheimer's disease (AD), focusing on the latest advancements in understanding its pathogenesis, diagnosis, and therapies. AD is characterized by the accumulation of β-amyloid (Aβ) plaques and hyperphosphorylated tau (pTau) tangles, leading to memory deterioration and cognitive impairments. The review highlights the role of risk factors such as *APOE* variants, infections, and inflammation in AD development. It discusses the molecular mechanisms underlying Aβ and pTau accumulation, including the amyloid cascade hypothesis and the involvement of neuroinflammation. The review also covers experimental models, diagnostic strategies, and peripheral biomarkers for AD. Additionally, it reviews the progress in disease-modifying drug development, including newly approved Aβ vaccines and novel strategies targeting pTau. The paper aims to provide a comprehensive update on AD research, from fundamental mechanisms to clinical diagnosis and therapies.This review provides an updated overview of Alzheimer's disease (AD), focusing on the latest advancements in understanding its pathogenesis, diagnosis, and therapies. AD is characterized by the accumulation of β-amyloid (Aβ) plaques and hyperphosphorylated tau (pTau) tangles, leading to memory deterioration and cognitive impairments. The review highlights the role of risk factors such as *APOE* variants, infections, and inflammation in AD development. It discusses the molecular mechanisms underlying Aβ and pTau accumulation, including the amyloid cascade hypothesis and the involvement of neuroinflammation. The review also covers experimental models, diagnostic strategies, and peripheral biomarkers for AD. Additionally, it reviews the progress in disease-modifying drug development, including newly approved Aβ vaccines and novel strategies targeting pTau. The paper aims to provide a comprehensive update on AD research, from fundamental mechanisms to clinical diagnosis and therapies.