With the usage of flash memory increasing, coupled with portable flash drives, and secure digital (SD) cards and other flash media becoming ubiquitous, all sorts of important information is often stored on them, including important and sensitive documents. Loss of data can often cause a heartache, and it can also cause practical problems, especially if these devices store important or sensitive information. Even for the case of NAND flash memory, which is referred to as a nonvolatile memory, the nonvolatility of the data stored on it is guaranteed only for a specified retention time. There is need to formulate techniques of data recovery in flash. Data recovery is the process of reclaiming data from damaged, failed, corrupted, or inaccessible secondary storage media when it cannot be accessed normally. The reasons for data recovery could
be physical damage to the storage device or logical damage to the file system that stops it from being mounted by the host operating system. This chapter presents a comprehensive analysis of flash memory and proceeds to describe a set of high-level and low-level approaches for data recovery of flash memory. Artifacts, triggered by flash-specific operations, including block erasing and wear leveling, are discussed and directions are given for enhanced data recovery from and analysis of data stored on flash memory. This chapter mainly consists of four parts. The first part discusses how computers store information. The second part discusses in-depth concepts relating to flash memory. The third part focuses on data recovery concept, and the fourth part presents various techniques of data recovery in flash memory. Therefore, we discover that, despite data loss being a problem, the good news is that most of the time data can be recovered.