Reviews
Part of 7 honest notes on consumer technology terms
Technology units compared: bits, bytes, hertz, and watts
Technology units compared: learn what bits, bytes, hertz, watts, watt-hours, pixels, and prefixes measure—and what those labels cannot tell you.
What to take away
- Unit symbols are case-sensitive, so Mb and MB are not the same quantity.
- Kilo, mega, giga, and tera are decimal prefixes; binary quantities have kibi, mebi, gibi, and tebi names.
- Hertz counts cycles per second but does not say what useful work happens in each cycle.
- Watts measure power, while watt-hours measure energy.
- USB-C identifies a connector shape, not one guaranteed data rate, display mode, or charging level.
For technology units compared side by side, the units and conditions must match. This table handles the most common consumer labels without treating one measurement as a complete performance score. The wider vocabulary those labels sit inside is set out in consumer technology terms.
Measurement comparison
Measures
- bit, b
- binary information
- byte, B
- eight bits
- Hz
- cycles per second
- W
- power
- Wh
- energy
- px
- picture elements
- ppi
- pixels per inch
- ms
- time in milliseconds
Useful question
- bit, b
- what network rate or encoded size is stated?
- byte, B
- how much file or storage data?
- Hz
- what clock, refresh, or signal frequency?
- W
- how quickly is energy being transferred now?
- Wh
- how much energy can be stored or used?
- px
- what addressable resolution?
- ppi
- how dense are pixels at a given size?
- ms
- what delay or response interval?
Does not prove
- bit, b
- delivered file rate by itself
- byte, B
- available user capacity
- Hz
- work completed per cycle
- W
- stored energy or runtime
- Wh
- actual runtime under every workload
- px
- sharpness, color, brightness, or panel quality
- ppi
- viewing quality at every distance
- ms
- total system latency unless the method covers it
Decimal prefixes
SI prefixes scale a unit by powers of ten. The standard metric prefix table defines kilo as 10^3, mega as 10^6, giga as 10^9, and tera as 10^12, written k, M, G, and T. Case matters: apart from the early prefixes kilo, hecto, and deca, multiplying prefixes take uppercase symbols while the dividing ones stay lowercase.
Binary prefixes scale by powers of 1024. Kibi, mebi, gibi, and tebi use Ki, Mi, Gi, and Ti. Some operating systems and sellers display storage with differing conventions, so two screens can show different-looking numbers for the same underlying byte count.
Bits per second versus bytes per second
Network service and interface ceilings often use Mb/s or Gb/s. File-transfer tools may use MB/s or GB/s. Since one byte contains eight bits, the numerical values differ by a factor of eight before overhead and other limits.
Bits versus bytes per second
- 8bits in one byte
- 125 MB/sraw ceiling of 1 Gb/s
- 1,000 MB/swrong reading of 1 Gb/s
A 1 Gb/s link therefore has a raw ceiling of 125 MB/s, not 1,000 MB/s. Real throughput is lower when framing, protocol work, storage speed, radio conditions, server capacity, or other traffic becomes the limit. Separating a plan's advertised number from a measured room result means isolating the failing layer.
Hertz in three common places
Processor clock rate, display refresh rate, and radio frequency can all use hertz, but they describe different cycles.
- GHz on a processor describes clock cycles, not instructions completed or application speed.
- Hz on a display describes refresh opportunities, not the frame rate supplied by content.
- GHz on a radio describes a frequency band, not a generation or speed guarantee.
Never compare two devices only because both show a larger Hz number.
Watts and watt-hours
Power equals energy transfer per unit of time. A 65 W adapter describes a possible power rate. A 65 Wh battery describes energy capacity. If a device averaged 10 W under one measured workload, an ideal 60 Wh store would suggest six hours, but conversion losses, reserve limits, aging, temperature, and changing workload alter actual runtime.
Voltage, current, protocol negotiation, cable rating, and device limits still govern compatibility. A higher-rated adapter does not make every device accept more power. Ratings, not plug shapes, are what make a safe charging kit work.
Pixels, resolution, and density
Resolution such as 2560 by 1440 describes an addressable grid. The same grid on two physical sizes produces different pixel density. Neither value describes color accuracy, contrast, motion behavior, brightness, reflections, scaling, or viewing distance.
For cameras, megapixels describe sampled image dimensions. Lens quality, sensor behavior, focus, movement, exposure, and processing affect the usable photograph.
USB connector and performance labels
USB-C is the reversible connector, and the C names only the physical shape. A port or cable may or may not implement a given data rate, USB Power Delivery, or a video alternate mode.
That is why basic USB 2.0 cables and full-featured ones look identical, while certified cables can carry official logo markings stating supported speed and power. A shape-only match is not enough for a demanding display, dock, storage drive, or charger.
Read the symbols on the port, cable, packaging, and product sheet. Then confirm both endpoint devices support the same function. Reading a connection as a chain from end to end is one step of how to read a technology specification sheet. The connection falls back to a mutually supported mode or may not perform the requested function.
Quick conversion habits
- Preserve the original value and unit.
- Convert both products to the same unit.
- Note whether the value is maximum, typical, minimum, or measured.
- Record test conditions.
- Translate the number into the intended task.
Common questions
Is 1 GB equal to 1,024 MB?
Under SI, 1 GB equals 1,000 MB. Binary quantities use GiB and MiB for 1,024-based steps.
Is a 120 Hz display always better than 60 Hz?
It offers a higher refresh ceiling, but content, response behavior, processing, and use determine the benefit.
Does every USB-C cable carry video?
No. Video support depends on the cable and both connected devices.
Can I estimate battery life from watt-hours?
Only with a realistic average power draw and allowance for losses and operating conditions.
