What is data persistence?

According to the Wikipedia article >:

  

It is characteristic of a state that survives the process that created it. Without this capability, the state would only exist in RAM, and would be lost when RAM stopped (turning off the computer, for example).

It's just a pretty name to say that you saved the data somewhere and it will not be lost when the computer is turned off (HDD, SSD, or even in the cloud, for example).

Normally it is linked to database, but of course it does not have to be in one, any type of application that writes anything so that this state can be retrieved later is doing persistence. It is not something that is connected to SQL, but of course SQL does persistence, especially in INSERT , UPDATE and DELETE .

The data in memory gets lost as soon as the program finishes.

In order for this data to not be lost, it must be recorded in a physical device.

Therefore, data persistence, in computing, refers to non-volatile data storage, for example, storage on a physical device such as a hard disk.