In addition to the local Taoism, Chinese is most familiar with Buddhism, although Buddhism is foreign, but in China has a very thick history and heritage, and even "Amitabha, Buddha bless" once became a mantra-style colloquialism, especially if the elderly people encounter something, they keep chanting this sentence in their mouths.
Then coupled with the vigorous popularization of Journey to the West, Chinese was even more familiar with the Buddha of Rulai, and even Sun Wukong could not escape his palm, leaving people with the basic impression of "the boundlessness of Buddhism".

Such as the Buddha
Anyone who has studied history knows that Buddhism originated in India, and the founder of Buddhism was Shakyamuni. That is to say, in the heyday of Indian Buddhism, the status of Shakyamuni was roughly equivalent to that of Confucius in Chinese history.
At the same time, we look at the Journey to the West, in the Journey to the West, the Buddha is the head of the Buddha's group of Buddhas, the lord of the Buddha's realm, with a supreme status and boundless mana. Therefore, there are many people who equate the Buddhist Shakyamuni with the Buddha of Rulai in traditional mythology, so are the Buddhas and Shakyamuni the same person?
Sakyamuni
Let's start with "Shakyamuni." Shakyamuni is not a name, such as our Confucius and Lao Tzu, nor is it a specific name, but a title that shows respect for them.
Shakyamuni's original name was Gautama Siddhartha, who belonged to the Shakya people of ancient India, and he was the prince of the Kapilava kingdom, with a very noble lineage, and Prince Siddhartha later became a Buddha under a Bodhi tree, so he was honored as Shakyamuni. Shakyamuni almost means "sage of the Shakya tribe.".
After the introduction of Buddhism to China, the title of Shakyamuni was generally "Buddha" or "Worldly Venerable", of course, he could also be called "Shakyamuni Buddha". So what does "Buddha" mean?
The word Buddha is transliterated from the Indian Sanskrit word, and in layman's terms, the meaning of the word Buddha is to represent wisdom and enlightenment, but the true connotation of the word Buddha is more than this, but we can understand it from the two aspects of wisdom and enlightenment, in the simplest words: the essence of the Buddha is wisdom, and its role is to make people "enlightened", which is the general interpretation of "Buddha".
After saying the Buddha, let's look at the meaning of "Rulai". Rulai ru is the meaning of true ru, representing the absolute truth, rulai, representing the saint who grasps the truth as the truth, so "rulai" is a title for the Buddha, just like we usually call the teacher, it is not a specific object, only when called Teacher Wang Teacher Zhang, there is an accurate title object.
Therefore, Shakyamuni Buddha, of course, can also be called Shakyamuni Rulai. So now we know that Buddha and Rulai are actually the same meaning, just like the master and the teacher, when we call "Rulai Buddha", we actually superimpose two titles with the same meaning, and there is no specific object, representing all the Buddhas.
However, because of the influence of Journey to the West, in the minds of Chinese, Rulai Buddha refers specifically to Shakyamuni, in fact, from a certain point of view, Journey to the West includes the Rulai Buddha in myths and legends, who is the eldest disciple of the Chaoquan Ancestor, and he and Bodhi Laozu are teachers and brothers.
Therefore, the Buddha of Rulai in journey to the West cannot be equated with Shakyamuni, who is the founder of Buddhism, and The Buddha of Rulai is the leader of the Buddha's realm in traditional Chinese mythology. Well, that's what today's sharing is, if you have better insights, you can leave a message in the comment area to add, and you are also welcome to criticize and correct.