Question 1

Why does a hard drive show less capacity than advertised?

Accepted Answer

The OS counts 1 GB as 1,024 MB (binary), while drive makers count 1 GB as 1,000 MB (decimal). A "1 TB" drive holds 1,000,000,000,000 bytes, which the OS reads as about 0.91 TiB — so roughly 7–10% seems to "vanish."

Question 2

What is the difference between GB and GiB?

Accepted Answer

A gigabyte (GB) is 10⁹ = 1,000,000,000 bytes; a gibibyte (GiB) is 2³⁰ = 1,073,741,824 bytes. The IEC introduced the "bi" prefixes in 1998, but everyday usage rarely follows them — Windows displays "GB" while actually meaning GiB, whereas macOS has used decimal GB since Catalina.

Question 3

How do I convert Mbit/s to MB/s?

Accepted Answer

There are 8 megabits in a megabyte, so a "100 Mbit/s" plan downloads at about 12.5 MB/s. A 1 GB file then takes roughly 1,024 / 12.5 ≈ 82 seconds. Providers quote megabits (a bigger number looks better), while files are measured in megabytes.

Question 4

How big are typical files?

Accepted Answer

A phone photo (12 MP JPEG) is 3–8 MB; a RAW photo 20–40 MB; one minute of 4K H.265 video 200–500 MB; one minute of 128 kbit MP3 about 1 MB. A AAA game runs 50–150 GB, and a Windows 11 installer image is about 5 GB.

Question 5

What does a terabyte mean in everyday terms?

Accepted Answer

One TB (1,000 GB by the manufacturer's count) holds roughly 250,000 photos, 500 hours of HD video, or 200 games. Laptop drives are typically 512 GB–1 TB, home NAS units 4–20 TB. For comparison, free Gmail storage is just 15 GB.

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