B-cell activation is a crucial process in the immune response, where B-cells, a type of white blood cell, recognize and respond to specific pathogens. This activation typically occurs when a B-cell binds to an antigen, which is a foreign substance like a virus or bacteria. The binding triggers the B-cell to proliferate and differentiate into plasma cells, which produce antibodies. Once activated, B-cells can also undergo a process called somatic hypermutation, enhancing the affinity of antibodies for their target. Additionally, some activated B-cells become memory cells, providing long-term immunity by quickly responding to future infections by the same pathogen.