The weatherman of CCTV was making a weather forecast with a black thing in his hand. What is this for?

When the program is broadcast, it needs to be held, mostly the remote control of the device that plays the role of prompt. The weather forecast should be illustrated with pictures and texts, and the background picture should be synthesized separately from the previous host. The host should point out that it takes effort to locate the specific location, and what he has will probably help to complete this work well.