How big is a terabyte in the text

How big are gigabytes, terabytes and petabytes?

You've no doubt heard the terms "gigabytes", "terabytes" or "petabytes", but what exactly do they mean for physical storage? Let's take a closer look at the memory sizes.

Words such as bytes, megabytes, gigabytes, and petabytes, all refer to the amount of digital memory. And sometimes they are confused with terms like megabit and gigabit. It is helpful to know what exactly these terms mean (and how they relate to one another) when comparing storage sizes on hard drives, tablets, and flash storage devices. This is also useful when comparing data transfer rates when purchasing Internet service or networking equipment.

Bits, Bytes, and Kilobytes

First, let's look at the basics of digital storage with some lower-level capacities.

The smallest storage unit is called bit (b). It is only capable of storing a single binary number - either a 1 or a 0. When we refer to a bit, especially as part of a larger word, we often use a lowercase "b" in its place. For example, a kilobit is one thousand bits and a megabit is one thousand kilobits. If we shorten something like 45 megabits, we are using 45 MB.

One step up is one byte (B). A byte is eight bits and is roughly what you need to store a single character of text. We use a capital letter "B" as the shortened form of the byte. For example, it takes about 10B to store an average word.

The next step of a byte is a kilobyte (KB), which is equal to 1,024 bytes of data (or 8,192 bits). We're shortening kilobytes to KB so that, for example, it would take around 10 KB to store a single page of plain text.

And with those smaller dimensions out of the way, now we can look at the terms you are more likely to hear when shopping for your gadgets.

Megabytes (MB)

There are 1,024 KB in a megabyte (MB). Until the late 1990s, common consumer products such as hard drives were measured in megabytes. Here are some examples of how much you can save in MB:

  • 1 MB = a book with 400 pages
  • 5 MB = An average 4 minute MP3 song
  • 650 MB = 1 CD-ROM with 70 minutes of audio

You will see number 1,024 frequently in the next few years sections. Typically, after the kilobyte level, each subsequent memory measurement is 1,024 of the next lower measurement. 1,024 bytes are one kilobyte; 1,024 kilobytes are one megabyte; and so on.

Gigabytes (GB)

So it should come as no surprise that there are 1,024 MB in one gigabyte (GB). GBs are still widely used when it comes to consumer storage capacity. Although most regular hard drives are measured in terabytes these days, things like USB drives and many solid-state drives are still measured in gigabytes.

Some examples from practice:

  • 1 GB = about 10 meters of books on a shelf
  • 4.7 GB = capacity of a DVD-ROM
  • 7 GB = How much data do you use per hour when streaming Netflix Ultra HD videos

Terabytes (TB)

One terabyte (TB) is 1,024 GB. Right now, TB is the most common unit of measure when it comes to regular hard drive sizes.

Some examples from practice:

  • 1 TB = 200,000 5-minute songs; 310,000 images; or films worth 500 hours
  • 10 TB = amount of data generated by the Hubble Space Telescope per year
  • 24 TB = number of video data uploaded to YouTube per day in 2016

Petabyte (PB)

There are 1,024 TB (or around a million GB) in a petabyte (PB). If trends continue, petabytes are likely to replace terabytes as the standard measure of consumer-level storage in the future.

Practical examples:

  • 1 PB = 500 billion pages of standard text (or 745 million floppy disks)
  • 1.5 PB = 10 billion photos on Facebook
  • 20 PB = The amount of data processed daily by Google in 2008

Exabyte (EB)

There are 1,024 PB in an exabyte (EB). Technology giants like Amazon, Google and Facebook (which process unimaginable amounts of data) usually only worry about this type of storage space at the moment. At the consumer level, some (but not all) file systems used by operating systems today have their theoretical limit somewhere in the exabytes

Practical examples:

  • 1 EB = 11 million 4K videos
  • 5 EB = All the words that have ever been spoken by mankind
  • 15 EB = Estimated total data from Google

This list could of course go on. The next three capacities on the list (for those of you who are curious) are zettabytes, yottabytes, and brontobytes. But to be honest, after the last exabytes you will run into astronomical storage capacities that are currently not very useful in practice.

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