The clinical manifestations of COVID-19, caused by the SARS-CoV-2 virus, exhibit a broad spectrum of symptoms ranging from asymptomatic or mild respiratory illness to severe pneumonia, acute respiratory distress syndrome (ARDS), multi-organ failure, and death. The incubation period typically ranges from 2 to 14 days, with a median of 4 to 5 days. Early symptoms often include fever, cough, and fatigue. Other common manifestations include dyspnea, myalgia, sore throat, and headache. Gastrointestinal symptoms, such as diarrhea, nausea, and vomiting, are also reported in some cases. Severe cases may progress to respiratory distress, requiring oxygen therapy and mechanical ventilation. Hypoxemia and respiratory failure are critical indicators of severe disease. The disease can also precipitate a hyperinflammatory response, leading to complications such as cytokine storm, which exacerbates lung injury and can lead to systemic inflammation affecting the heart, kidneys, and liver. Cardiovascular manifestations include myocarditis, arrhythmias, and acute cardiac injury. Coagulopathy, characterized by elevated D-dimer levels and thrombosis, is a significant concern, increasing the risk of venous thromboembolism and stroke. Neurological symptoms range from anosmia and ageusia to more severe conditions such as encephalopathy, seizures, and Guillain-Barré syndrome. Skin manifestations, including rashes, urticaria, and "COVID toes" (chilblain-like lesions), have been observed. The severity and range of symptoms vary widely, influenced by factors such as age, comorbidities, and immune response. Older adults and those with underlying conditions like hypertension, diabetes, and obesity are at higher risk for severe disease and mortality. Understanding the diverse clinical manifestations of COVID-19 is crucial for timely diagnosis, management, and therapeutic intervention. Continuous research is necessary to unravel the pathophysiological mechanisms underlying these manifestations and to develop effective treatment strategies.