PS3 uses a standard Laptop Harddrive and the PS3 has been designed to allow you to upgrade the harddrive with a 2.5" internal Serial ATA HDD see related link from Playstation support.
Quote from related link,"The PS3 system hard disk drive (HDD) is removable and upgradeable. An upgrade can be performed by removing the hard drive and replacing it with a larger capacity drive. Please be advised that if you replace the hard drive, the data that was on the original hard drive will not show up on the PS3 unless you manually back up the data and transfer it to the replacement hard drive."
For complete instructions on how to properly upgrade the hard disk drive, the related link has more information.
So they can sell the ps3's at different prices.
Yes. Your ps3 will notice nothing
Yes. Any 2.5" (laptop) SATA drive can be used with a PS3.
yes the PS3 uses standard laptop harddrives and was designed to be able to add a larger HDD
Definitely Microsoft for computers and Xbox 360 for ps3, Sony
PS3 don't use special harddrives like Xbox 360 and instead use a standard notebook harddrive that can be purchased in most computer departments
You can purchase an external hard drive from a variety of places, including retail and online stores. Most stores that sell electronics will have an external hard drives in many different sizes. Online stores, such as DiscounTechnology, also carry external hard drives. Prices vary depending on brand, model, and storage space of the external hard drive, though Sony recommends Seagate external Hard Drive due to it's higher compatibility than other external hard drives with the PlayStation 3 system. Be sure that when you buy one, you have one equal to or greater than the total capacity of your current PS3 to ensure that your data is transferred. If you do not have enough storage space, your data will not transfer at all.
One can sell HP hard drives at multiple online retailers. Two of the most popular retailers would be eBay and Best Buy. One can also sell a used HP hard drive to Power Source.
Seagate has been in the bussiness for a long time and sell fast and reliable hard drives.
Yes, but they are smaller in GB, but all use standard laptop size
If it's not already there after the hard drive replacement, then it should be on the backup you made, if you made a backup, if not, swap hard drives, run the backup wizard, reswap hard drives, restore from backup
The current PS3 hard drive sizes are 120GB and 250GB. Past models have included 20, 40, 60, 80, and 160 GB hard drives.