The threshold of folk songs is not high, and a guitar can become a song after a period of affection. Simply put, if you know a few chords, you can use them to express life, praise love or vent your anger. But the tone of this music form should be poetic.
Whether it is folk songs adapted from local folk songs or incorporated into world music elements, such as Wild Child and Traveler, or urban folk songs telling city stories, such as Wan Xiaoli, Chuanzi, Ming Jiang, and Dongye folk songs. Their music style is closer to modern pop music ... You can intuitively judge that this is a folk song.
Then back to the question of "what is a folk song", I don't think it is necessary to give it a precise definition. It always quietly pokes the listener's heart, lyrics or poems or customs, but it is always a sincere gesture of not faking. It is a collection of unspeakable spiritual feelings. You can say that this is an object-chanting poem, which means that this is a dialogue with melody.
Folk songs, simple and easy to sing, wrap the singer's most authentic feelings and have a never-artificial attitude. This is the folk sketch in my eyes.
Popular folk songs endowed with national colors are called folk songs or ballads. Folk songs have a long history, so most of their authors are unknown. Folk songs are rich in content, including religion, love, war, labor, drinking, dancing, festivals and so on. Folk songs express the feelings and habits of a nation, so each has its own unique scale and emotional style. For example, the prosperity of French folk songs, the enthusiasm of Italian folk songs, the simplicity of English folk songs, the indignation of Japanese folk songs, the wildness of Spanish folk songs and the tears of China folk songs all show strong national temperament and color.