"How can I get back my deleted data from hard disk (computer), memory card?"
Disk Digger is another free data recovery software which recover files from any type of media including USB flash drives, memory cards (SD, Compact Flash, Memory Stick, etc), and your hard drive also.
>> This program can recover deleted files including photos, videos, music, documents, and other formats also.
>> This is a free portable tool, i.e. it does not require any installation.
>> When you are using Disk Digger you need to select the drive and file types and click Next and retrieve the file from the list is files shown.
You can get it from Here