Answer Description

Many mobile devices like smart phones and tablets use eMMC (embedded Multi Media Card) as an internal storage mechanism. eSata is not commonly found in these devices and is a not a storage medium but a bus interface for transmitting data. SDHC and Micro-SD are memory cards and not internal components.

Wikipedia

The MultiMediaCard, officially abbreviated as MMC, is a memory card standard used for solid-state storage Unveiled in 1997 by SanDisk and Siemens AG, MMC is based on a surface-contact low pin-count serial interface using a single memory stack substrate assembly, and is therefore much smaller than earlier systems based on high pin-count parallel interfaces using traditional surface-mount assembly such as CompactFlash Both products were initially introduced using SanDisk NOR-based flash technology MMC is about the size of a postage stamp: 24 mm × 32 mm × 14 mm MMC originally used a 1-bit serial interface, but newer versions of the specification allow transfers of 4 or 8 bits at a time