The Institute of Electrical and Electronics Engineers(IEEE) was formed by an amalgamation of American Institute of Electrical Engineers and the Institute of Radio Engineers in the year 1963.
Fig 1. IEEE logo 
It develops global standards for industries like power & energy, telecommunication, automation, nanotechnology, robotics, information technology etc. The drafting of the standards is done based on the participation of experts from across the globe.
It is a standard which deals with local area networks and metropolitan area networks.
Within this standard, there is IEEE 802.11 which is meant for implementing Wireless Local Area Network(WLAN) computer communication in various frequencies, including but not limited to 2.4, 5, and 60 GHz frequency bands which are utilized as home & office networks to allow laptops, printers, and smartphones to talk to each other and access the Internet without connecting wires
Fig 2. WLAN(IEEE 802.11) 
What is IEEE 802.11bb??
It is an amendment to the IEEE Std. 802.11 which has been approved by the IEEE Standards Association Board in May 2018 for the creation of the specifications for Light based Communication.
Fig 3. Visible Light Spectrum for communication
This amendment specifies a new PHY(Physical Layer) and modifications to the IEEE 802.11 MAC(Medium Access Control) that enable operation of wireless light communications (LC)
The new PHY will provide:
- Uplink/Downlink within a band of 380-5000 nm
- All PHY modes of operation must achieve a minimum single-link throughput of 10 Mb/s and at least one mode of operation that achieves single-link throughput of at least 5 Gb/s, as measured at the MAC data service access point (SAP),
- Interoperability among solid state light sources with different modulation bandwidths
In this way, the light spectrum can be used to provide data off-loading and link aggregation in conjunction with other 802.11 technologies in a globally harmonized and license-exempt spectrum.
VLC(also referred to as “Li-Fi”) can be implemented using standard off-the-shelf visible light LEDs to transmit data. Thus there is minimal impact on the infrastructure.
The emitted light is modulated to transmit data at a high speed without any perceived change in light amplitude.
Fig 4. Implementation of VLC 
Demonstration of VLC/Li-Fi
With the market size for Visual Light Communication(VLC) expected to be over $75.5 billion by 2023 owing to the sale of over 550 million LED lights at a Compound Annual Growth Rate(CAGR) of 13%, standardizing of VLC as a part of 802.11 will help in accelerating the products to the market and obtaining necessary certification(e.g. Wi-Fi Alliance).