In June 2025, 3GPP is scheduled to officially launch its 6G research project, marking the global evolution of 6G from a visionary stage toward a new phase characterized by critical technological development, standardization, and practical applications. 6G networks leverage larger antenna apertures and higher frequency bands (e.g., mid-bands, millimeter waves, terahertz) to prioritize near-field characteristics. The integration of reconfigurable intelligent surfaces (RIS), extremely large aperture arrays (ELAA), movable antenna (MA), and cell-free architectures will expand near-field dominance, creating a near-ubiquitous near-field propagation environment. From the perspective of spatial resource utilization, while conventional far-field systems can only separate signals in the angular domain, the transition toward near-field operation enhances the capacity to exploit the depth domain in wireless communications. Near-field technology, equipped with numerous antennas, has attracted increasing attention in 6G networks for its potential to provide higher data rates through beam focusing, precise angular-depth localization and sensing, as well as efficient wireless power transfer. Near-field research reveals a paradigm shift in understanding the propagation characteristics of electromagnetic waves. These waves can no longer be simply regarded as plane waves; instead, they should be accurately modeled as spherical waves. This revised modeling highlights the importance of previously negligible electromagnetic phenomena in system modeling and design. These phenomena include spatial non-stationarity, finite-depth beam focusing, tri-polarization, and evanescent waves. Beyond conventional wave modeling, near-field research unlocks access to novel wavefronts, such as non-diffracting beams (including self-healing Bessel beams and curved Airy beams). Traditional communication algorithms, tailored for far-field conditions, may underperform in 6G near-field environments, and model-agnostic algorithms might not fully capitalize on these new characteristics. This white paper reviews the typical application scenarios for near-field technologies in future wireless networks. It then delves into the fundamental electromagnetic principles underlying near-field effects and their disruptive impact on communication systems, systematically elucidating the constraints and enablers imposed on system architecture design—focusing on the core metrics of degrees of freedom and capacity. Recognizing that channel characterization is foundational to communication system design, the paper provides a detailed discussion of near-field channel research paradigms from both measurement and modeling perspectives, and further explores key technologies such as channel estimation, beamforming, and codebook design. Additionally, it prospectively examines the collaborative innovation between near-field technologies and other fields, including integrated sensing and communication, wireless power transfer, and physical layer security. At the engineering practice level, the latest advances in 6G spectrum allocation, the implementation of near-field propagation techniques, and network deployment strategies are highlighted. This white paper aims to establish a unified cognitive framework for near-field technologies, bridging theoretical advances with standardization efforts and engineering implementation.