How did Oracle Bone Inscriptions come from?

A is the shell of a tortoise, and the bones are the shoulder blades of animals such as cattle and sheep. Ancestors used them in the Shang Dynasty as early as 3,500 years ago to write "Oracle Bone Inscriptions", which is now called "Oracle Bone Inscriptions". Although Oracle Bone Inscriptions is very different from modern Chinese characters, it is the oldest known Chinese character in China. Oracle Bone Inscriptions is the earliest extant material. Since 1899, archaeologists have unearthed more than 60,000 pieces of Oracle bones/kloc-0 in Anyang, Henan, Jinan, Shandong and Binxian, Shanxi, which is very helpful for people to understand the society and culture at that time. Oracle bones are limited in source, which is not convenient for carving, carrying and keeping.