Proprietary memory card formats for use in professional audio and video, such as P2 and SxS, are faster, but physically larger and more costly.

In November 2010, SanDisk, Sony and Nikon presented a next generation card format to the CompactFlash Association.

[6][7] With potential read and write speeds of 1 Gbit/s (125 MB/s) and storage capabilities beyond 2 TiB, the new format is aimed at high-definition camcorders and high-resolution digital cameras, but the new cards are not backward compatible with either CompactFlash or CFast.

CompactFlash was originally built around Intel's NOR-based flash memory, but has switched to NAND technology.

CF cards with flash memory are able to cope with extremely rapid changes in temperature.

The IBM Microdrive format, later made by Hitachi, implements the CF Type II interface, but is a hard disk drive (HDD) as opposed to solid-state memory.

[19] A direct motherboard connection is often limited to 33 MB/s because IDE to CF adapters lack high speed ATA (66 MB/s plus) cable support.

Many 1-inch (25 mm) hard drives (often referred to by the trademarked name "Microdrive") typically spin at 3600 RPM, so rotational latency is a consideration, as is spin-up from standby or idle.

The CF 5.0 Specification supports capacities up to 128 PiB using 48-bit logical block addressing (LBA).

SanDisk announced its 16 GB Extreme III card at the photokina trade fair, in September, 2006.

[28] Several companies make adapters that allow CF cards to be connected to PCI, PCMCIA, IDE and SATA connections,[29] allowing a CF card to act as a solid-state drive with virtually any operating system or BIOS, and even in a RAID configuration.

CompactFlash cards that use flash memory, like other flash-memory devices, are rated for a limited number of erase/write cycles for any "block."

When using CompactFlash in ATA mode to take the place of the hard disk drive, wear leveling becomes critical because low-numbered blocks contain tables whose contents change frequently.

The more advanced CompactFlash cards will move data that rarely changes to ensure all blocks wear evenly.

As a flash memory device is solid-state, it is less affected by physical shock than a spinning disk.

The possibility for electrical damage from upside-down insertion is prevented by asymmetrical side slots, assuming that the host device uses a suitable connector.

[35] However, the manufacturer's warning on the flash memory used for ReadyBoost indicates a current draw in excess of 500 mA.

[36] Although FAT16 is more wasteful of disk space with its larger clusters, it works better with the write strategy that flash memory chips require.

CompactFlash cards are often used instead of hard drives in embedded systems, dumb terminals and various small form-factor PCs that are built for low noise output or power consumption.

CFast 1.0/1.1 supports a higher maximum transfer rate than current CompactFlash cards, using SATA 2.0 (300 MB/s) interface, while PATA is limited to 167 MB/s using UDMA 7.

[42] At CES 2009, Pretec showed a 32 GB CFast card and announced that they should reach the market within a few months.

[45] On 7 April 2014, Blackmagic Design announced the URSA cinema camera, which records to CFast media.

A strong incentive to change to CFast for embedded electronics companies using designs based on Intel PC architecture is the fact that Intel has removed native support for the (P)ATA interface a few design platforms ago and the older CPU/PCH generations now have end-of-life status.

[48] In April 2017, the version 1.0 of the CFexpress specification was published, with support for two PCIe 3.0 lanes in an XQD form-factor for up to 2 GB/s.

Manufacturers of CompactFlash cards such as Sandisk, Toshiba, Alcotek and Hynix offer devices with Type I slots only.

[53] Microdrive was a brand of tiny hard disks—about 25 mm (1 inch) wide—in a CompactFlash Type II package.

IBM sold its disk drive division, including the Microdrive trademark, to Hitachi in 2002.

[54] As mechanical devices, CF HDDs drew more current than flash memory's 100 mA maximum.

However, CF HDDs had a longer lifespan of write cycles than early flash memories.

[citation needed] The iPod mini, Nokia N91, iriver H10 (5 or 6 GB model), LifeDrive, Sony NW-A1000/3000 and Rio Carbon used a Microdrive to store data.