A 2.5-inch hard drive is a type of storage device commonly used in laptops and portable external drives. Its compact size allows it to fit easily into slim devices, making it ideal for mobile computing. These drives typically use either HDD (hard disk drive) or SSD (solid-state drive) technology, with SSDs offering faster data access speeds and greater durability. The 2.5-inch form factor is standardized, meaning it can be easily replaced or upgraded in compatible devices. These drives usually connect via SATA (Serial ATA) interface, providing a reliable way to transfer data between the drive and the computer.