What type of software is able to recover lost data from Mac hard disk drive?

[maithli]

I have lost files from Mac HDD. My Mac system hard disk drive formatted accidentally. That's why all files which were stored on it have been lost. I just want to about any software which helps me to get back lost files from formatted Mac HDD?

[4wd]

TestDisk can find partitions for most filesystems and is available for Mac OSX - it may help you recover the whole HDD.

You can run it over the drive to see if it finds anything but you'll need another HDD to recover anything to.

Otherwise there's the commercial R-Studio.

[tomos]

^presumably TestDisk would need to be run from something bootable - a recovery-disk
http://www.cgsecurity.org/wiki/TestDisk_Livecd