The main purpose of my thesis is to introduce the topic of first language acquisition. Mainly the acquisition of the Hungarian language compared to the English in various cases. I show the different stages of how a child starts to acquire his or her mother tongue. I will show the main theories of this topic including the beginning of this process. I will introduce the theory of two significant linguists like Noam Chomsky and Burrhus Skinner. To make it more understandable I give examples based on my own experiences.