The NF-κB (nuclear factor kappa-light-chain-enhancer of activated B cells) transcription factor family plays a central role in cell death, adhesion, immunity, inflammatory responses, and cell proliferation and differentiation. Family members include RelA, RelB, c-Rel, NF-κB1, and NF-κB2, forming different dimers, whose activity is inhibited by the IκB protein family. Upon encountering activation signals such as inflammation and cytokines, IκB degradation occurs, leading to the translocation of NF-κB into the nucleus, where it activates gene expression. The localization and activity of NF-κB are finely regulated, reflected in its involvement in diverse signaling pathways and tissue-specific gene expression. Imbalance in its regulation and gene mutations are closely associated with diseases such as inflammation, autoimmune disorders, and cancer, highlighting the importance of NF-κB as a therapeutic target.