In Excel, the colon (:) is used to specify a range of cells. For example, A1:A10 refers to all cells from A1 to A10. It is commonly used in functions like SUM(A1:A10) to indicate the range of cells to be processed.

A pen drive, also known as a USB flash drive, is a portable storage device used to store, transfer, and retrieve digital data.

A light pen is an input device used to interact with the computer by detecting light on a screen. In contrast, devices like monitor, printer, and plotter are output devices that display, print, or produce data generated by the computer.

Windows 10 is a widely used operating system developed by Microsoft. It is part of the Windows family of operating systems and is designed for personal computers, tablets, and other devices.

Among the listed storage devices, SSD (Solid State Drive) is the most expensive in terms of cost per GB, especially for a capacity of 256 GB. SSDs offer faster read/write speeds, improved durability, and energy efficiency compared to traditional hard drives, floppy disks, or pen drives, justifying their higher cost.