Visual working memory (VWM) capacity is a key aspect of cognitive function, closely linked to overall cognitive ability and measurable through various tasks. Recent research indicates that VWM capacity is constrained by a limited number of discrete representations rather than an infinitely divisible resource. Individual differences in VWM capacity reflect true storage limitations or variations in efficient use of memory. VWM is essential for visual tasks, enabling the maintenance of visual information during eye movements and supporting higher-level visual processing. Studies show that VWM capacity is influenced by factors such as attentional control and filtering of irrelevant information. Neural mechanisms, including sustained neural activity and oscillations, underlie VWM capacity. Research suggests that VWM capacity is limited by the number of discrete items that can be maintained, with evidence supporting discrete slot models over continuous resource models. Individual and group differences in VWM capacity are significant, with implications for cognitive function and disorders such as schizophrenia. The capacity of VWM is also linked to broader cognitive abilities, and understanding its mechanisms can lead to insights into cognitive differences and potential interventions.Visual working memory (VWM) capacity is a key aspect of cognitive function, closely linked to overall cognitive ability and measurable through various tasks. Recent research indicates that VWM capacity is constrained by a limited number of discrete representations rather than an infinitely divisible resource. Individual differences in VWM capacity reflect true storage limitations or variations in efficient use of memory. VWM is essential for visual tasks, enabling the maintenance of visual information during eye movements and supporting higher-level visual processing. Studies show that VWM capacity is influenced by factors such as attentional control and filtering of irrelevant information. Neural mechanisms, including sustained neural activity and oscillations, underlie VWM capacity. Research suggests that VWM capacity is limited by the number of discrete items that can be maintained, with evidence supporting discrete slot models over continuous resource models. Individual and group differences in VWM capacity are significant, with implications for cognitive function and disorders such as schizophrenia. The capacity of VWM is also linked to broader cognitive abilities, and understanding its mechanisms can lead to insights into cognitive differences and potential interventions.