The cultivation of algae, encompassing diverse microalgae and macroalgae species, has garnered significant attention due to its potential applications in biofuel production, food and feed supplements, wastewater treatment, and pharmaceuticals. Modern advancements in biotechnology and engineering have revolutionized this field, enabling large-scale algae production to meet the demands of a growing population. Algae are highly efficient at converting solar energy into organic molecules through photosynthesis, making them a promising resource for sustainable solutions in multiple industries. This chapter explores methods for mass cultivation of algae, highlighting the importance of selecting suitable algal strains with high growth rates and resilience to environmental fluctuations. Techniques such as bioprospecting, high-throughput screening, genetic, and metabolic engineering are employed to enhance desirable traits in algal strains, thereby improving biomass yield and the production of valuable compounds. Nutrient management is critical, with specific formulations tailored to the nutritional needs of different microalgae species and cultivation objectives. Factors such as light intensity, temperature, and pH significantly influence microalgal growth, necessitating precise control to optimize productivity. Technological innovations, including the use of pulsing blue light and carbon capture from industrial emissions, are advancing the efficiency and sustainability of algae cultivation. The integration of omics technologies provides insights into the molecular mechanisms governing algal growth, aiding in the development of optimized cultivation strategies. The future of algae cultivation is promising, with ongoing efforts to enhance production efficiency, environmental sustainability, and economic viability. Mass cultivation of algae is poised to play a crucial role in addressing global challenges related to energy, food security, and environmental conservation.