Generally speaking, feeding is a process and swallowing is an action. Swallowing is part of the feeding process and refers to a series of continuous actions that occur when food reaches the stomach through the mouth, pharynx and esophagus. When people see food, visual and olfactory sensory information is transmitted to the brain, and the central nervous system analyzes the received information to form a cognitive understanding of food and make instructions related to preparing to “eat”, which we call the “cognitive period”. Then, the food is put into the mouth and the physical and chemical properties of the food stimulate the receptors of the oral cavity and tongue and other swallowing organs, which then transmit the information obtained to the swallowing center. The tongue is involved in the agitation of food and interacts with the cheek to place food between the upper and lower molars, making it easier to chew food; at the same time, the tongue root comes in contact with the soft palate, forming a tongue-palate connection to avoid premature entry of food into the pharynx. Through these activities the food becomes a swallowable mass, a process we usually call “oral preparation”. Then the lingual muscles contract and the tip of the tongue lifts up to the upper alveolar barrel, forming a depression in the middle part of the tongue into which the food mass is pushed; the lingual muscles continue to contract and lift up, bringing most of the tongue body into contact with the hard palate and pushing the food mass toward the root of the tongue, which becomes the “oral phase”. Immediately afterwards, the food mass continues to move forward, while the tongue-palate connection gradually disappears, the posterior part of the tongue descends, and the soft palate moves backward and upward, contacting the posterior pharyngeal wall and closing the nasopharynx to prevent food from entering the nasopharynx and increasing the pressure in the pharynx. At this point the food mass is pushed into the oropharynx due to the movement of the tongue, followed by the initiation of the gag reflex, which causes the gag reflex (this reflex is not under conscious control). After the reflex is activated, the laryngeal complex of the hyoid bone moves forward and upward under the action of the supraglottis muscle and the thyroid hyoid muscle, which is the upward lift of the “laryngeal node” that we can see, about 1-50 px. After the larynx starts to lift, the vocal cords move toward the midline, the real and false vocal cords close one after another, and the laryngeal cavity closes. Due to the pull of the laryngeal lift, the arytenoid cartilage moves forward against the root of the epiglottis cartilage, closing the vestibule of the larynx. At the same time, the tongue root continues to contract downward and backward, and the pharyngeal constriction muscle contracts toward the middle of the pharyngeal cavity, gradually closing the pharyngeal cavity from top to bottom and pushing the food mass to continue to transport to the pharynx, which completes the short but complex “pharyngeal phase”. Then the food mass passes through the epiglottis and the pear-shaped crypt to reach the cricopharyngeal muscle. When the food mass enters the esophagus, the structure of the larynx is reset and breathing resumes. The esophageal mass continues to move downward in the “peristaltic” movement of the esophagus and finally reaches the stomach, where the “esophageal phase” ends, i.e., a swallow is successfully completed. Through the above swallowing process, we understand that swallowing is a series of complex and continuous movements, and the swallowing process is artificially divided into different periods according to the location and anatomical structure of the food mass. We present it in five phases: cognitive phase, oral preparation phase, oral phase, pharyngeal phase and esophageal phase. The cognitive phase is the process from seeing something to eating, which is related to the higher centers of the brain and is controlled by the consciousness. The oral preparation period is from the time food is placed in the mouth to the time it is chewed into a food mass suitable for swallowing, and is controlled by consciousness. The oral phase is the period from the formation of the food mass to its being pushed into the pharynx. This phase is under the control of consciousness. The pharyngeal phase is the process from the initiation of the swallowing reflex to the passage of the food mass through the cricopharyngeal muscle. This phase is a series of reflex activities, and once the swallowing reflex is initiated, swallowing activity will not be under conscious control. The point of initiation of the gag reflex can be any point where the root of the tongue intersects the mandible. As stated above, the pharyngeal phase is a rapid and complex activity that can be completed in less than 1 second. The esophageal phase is the passage of the food mass through the esophagus into the stomach. This phase is also not governed by consciousness. The “peristalsis” is a waveform movement of the esophagus in which the food mass enters the esophagus with a diastolic wave at the lower end and a contraction wave at the upper end, which, together with the gravitational force of the food mass, propels the food downward. This period is about 8-20 seconds. Understanding the physiological process of normal swallowing is fundamental to the assessment and treatment of swallowing disorders.