Final answer:
In the FAT file system, when a file is deleted, the directory entry is marked as free and the sectors storing the data are made available for new data, but the actual content remains on the disk until overwritten.
Step-by-step explanation:
When a file is deleted in the File Allocation Table (FAT) system, the actual data of the file isn't immediately removed from the disk. Instead, the system marks the first character of the file's directory entry with a special character (usually E5h in hex), which indicates to the system that the space occupied by the file is now available for new data. The sectors in the FAT that were previously allocated to the file are marked as free, meaning they can be used to store data from other files in the future. Until the space is overwritten by new data, it is possible to recover the deleted file using data recovery software. This is because the content remains on the disk until it is explicitly overwritten.