ASIC (Application Specific Integrated Circuit) is a type of integrated circuit (IC). In order to run it, you need a PC, etc.
In the case of Bitcoin and other cryptocurrencies, it means a chip dedicated to mining.
ASIC with processing speeds far exceeding those of CPU are being deployed in bitcoin mining operations.
Individuals and companies that participate in mining invest heavily to prepare large numbers of ASICs. The ASICs are specialized for bitcoin mining, and they enable the mining process to be as fast as possible.
ASICs are expensive and, like CPUs, cannot be converted to other uses. Therefore, when the price of bitcoin falls, there is a disadvantage in that the amount of reward will decrease.