Quickly transfer files to and from your laptop or desktop using this SanDisk Ultra SDCZ48-064G-A46 USB 3.0 flash drive that features a read speed of up to 80MB/sec. The 64GB capacity offers ample storage space. (Ten times faster than USB 2.0 drives. Write speeds up to 10 times faster than Cruzer USB 2.0 drive.)* *USB 3.0 port required. Based on internal testing; performance may be lower depending upon host device.
Universal Serial Bus (USB) is a standard that defines both communication protocols and physical connections for data transfer. Using thumb drives based on this standard ensures they work with a broad range of devices, making it simple to show digital pictures on a USB-enabled television, transfer files between Apple and Microsoft computers or use your saved game on a friend's gaming console. These devices also offer plug-and-play compatibility with most operating systems and require no additional software to access the storage they provide.
Some file systems are designed to distribute usage over an entire memory device without concentrating usage on any part (e.g., for a directory) to prolong the life of simple flash memory devices. Some USB flash drives have this 'wear leveling' feature built into the software controller to prolong device life, while others do not, so it is not necessarily helpful to install one of these file systems.[39]
“The solid state flash drive can theoretically achieve incredibly high transfer speeds, blurring the line between an external solid state drive and a flash drive,” our tester raved. He did note he was “unable to reach higher than half the listed read and write speeds.” However, he explained, “The Extreme Pro is still very fast compared to other USB 3.0 flash drives.” In the end, our tester recommended this flash drive “with the caveat that there's a good chance you won't see those 300+ MB/s transfer speeds.” He also added that for just a little more, you could invest in an external hard drive—if the ultra-compact form factor isn’t important in your buying decision.
Universal Disk Format (UDF) version 1.50 and above has facilities to support rewritable discs like sparing tables and virtual allocation tables, spreading usage over the entire surface of a disc and maximising life, but many older operating systems do not support this format. Packet-writing utilities such as DirectCD and InCD are available but produce discs that are not universally readable (although based on the UDF standard). The Mount Rainier standard addresses this shortcoming in CD-RW media by running the older file systems on top of it and performing defect management for those standards, but it requires support from both the CD/DVD burner and the operating system. Many drives made today do not support Mount Rainier, and many older operating systems such as Windows XP and below, and Linux kernels older than 2.6.2, do not support it (later versions do). Essentially CDs/DVDs are a good way to record a great deal of information cheaply and have the advantage of being readable by most standalone players, but they are poor at making ongoing small changes to a large collection of information. Flash drives' ability to do this is their major advantage over optical media.
Counterfeit USB flash drives are sometimes sold with claims of having higher capacities than they actually have. These are typically low capacity USB drives which are modified so that they emulate larger capacity drives (for example, a 2 GB drive being marketed as a 64 GB drive). When plugged into a computer, they report themselves as being the larger capacity they were sold as, but when data is written to them, either the write fails, the drive freezes up, or it overwrites existing data. Software tools exist to check and detect fake USB drives,[43][44] and in some cases it is possible to repair these devices to remove the false capacity information and use its real storage limit.[45]
USB flash drives are often used for storage, data back-up and transfer of computer files. Compared with floppy disks or CDs, they are smaller, faster, have significantly more capacity, and are more durable due to a lack of moving parts. Additionally, they are immune to electromagnetic interference (unlike floppy disks), and are unharmed by surface scratches (unlike CDs). Until about 2005, most desktop and laptop computers were supplied with floppy disk drives in addition to USB ports, but floppy disk drives became obsolete after widespread adoption of USB ports and the larger USB drive capacity compared to the 1.44 MB 3.5-inch floppy disk.
Installers of some operating systems can be stored to a flash drive instead of a CD or DVD, including various Linux distributions, Windows 7 and newer versions, and macOS. In particular, Mac OS X 10.7 is distributed only online, through the Mac App Store, or on flash drives; for a MacBook Air with Boot Camp and no external optical drive, a flash drive can be used to run installation of Windows or Linux.
For computers set up to be bootable from a USB drive, it is possible to use a flash drive containing a bootable portable operating system to access the files of the computer, even if the computer is password protected. The password can then be changed, or it may be possible to crack the password with a password cracking program and gain full control over the computer. Encrypting files provides considerable protection against this type of attack.
USB 2.0 flash drives have a transfer rate of up to 480Mbps, while USB 3.0 flash drives allow for transfer rates 10 times faster — up to 4.8Gbps. However, you can only take advantage of this higher speed if your device has a USB 3.0 port. Although USB 3.0 flash drives and other devices are backwards compatible with USB 2.0 ports, they will only operate at a USB 2.0 rate.
