Speech is a complex foundation of communication among people and a very important factor in the overall development of a child. In order for speech to be realized and for it to circulate among people, it must first be addressed to someone, but it also needs to be reciprocated. Speech is a complex neurological process in which brain functions are related to the structures and development of speech. Neurological theories generally prove that the development of language and speech is determined anatomically, neurobiologically and genetically. Moreover, speech can be classified as part of culture since it develops not only by speaking but also by listening. Speech conveys culture; therefore, the way of communication depends on the type of character which is popularized in the cultural area. It can be claimed that speech itself is an astonishing process. It is a process in which each person has their own individual role. As we grow, so does the ease of speech acquisition, which is crucial for our survival and relationships with people. However, difficulties can arise in the development of speech and language. These difficulties are also affected by various possible impairments such as hearing impairment, pervasive developmental disorder, specific language disorders, or disorders of the pace and rhythm of speech, which are characterized by a slow pace of speech and language development.Furthermore, some children and people are also acquainted with pronunciation disorders that occur for a variety of reasons. They lack the ability to pronounce certain sounds correctly, mix them with each other, or omit them completely. Improper pronunciation of syllables and whole words is also a disorder, while the vocabulary itself is rich and the speech is grammatically correct. There are many causes for speech development difficulties. The causes can be biological and social, but they are very intertwined in the whole story of speech development.The most important thing is to timely notice and react to any obstacle in the speech development. In other words, the truth about the state of a child’s speech development should by no means be ignored or rejected. It should be kept in mind that speech development takes place from the very conception of a child who has not yet arrived in the world. Thus, Posokhova roughly wanted to stage the importance of the role of adults in child speech development and stated that one influences a child’s speech development "20 years before their birth".