Nearsighted glasses are eyeglasses prescribed for the correction of myopia, and the sphere power on prescription sheet usually begins with "-". Myopia is very common, irregular reading posture, prolonged use of electronic screens are the causes of myopia.
Farsightedness is generally the inability to see near things such as letters in a book, while nearsightedness is the opposite of not being able to see far away. However, the exact prescription needs to be measured by a doctor.
Nearsighted glasses are custom-made to solve the problem of not being able to see far away, so you should wear them most of the time, but you can also take them off at appropriate times for eye rest.