They are those units of measurement that allow to determine how much space is available in a memory unit.
It is called a measure of storage to record the space that is on a given device to record data and information permanently or temporarily.
It can also be understood as that practice that is carried out with the interest of optimizing performance and taking advantage of all the space that exists within a unit.
In computing, there are different storage devices that facilitate the conservation of information, either inside the computer or outside, such as a portable memory. The devices can be both a memory or hard disk, a disk or CD-ROM, a flash or portable memory, a DVD and several others. In these the information can be stored temporarily or temporarily or permanently.
When they talk to us about "mega", "gigas" and "teras", many times we lose our bearings on whether they are talking about a large or small storage space. To clarify, here is a guide on how to understand storage measurements on hard drives, USB sticks and other computer media.
The most basic unit is the bit, which corresponds to a single unit of information that can present only one of two possible states, 0/1 (or yes / no, black / white, ...).
We will seldom refer to bits when we talk about storage, and if they indicate that the system is 32 or 64 bits, they are not referring to anything that refers to storage, but to the word width of the bus.
The next storage unit is the byte, consisting of eight bits.
The bytes will not be mentioned when we talk about storage units, as it is a very minimal unit, and it is used to store a letter, number or symbol.
It is obvious that any computer system will need to store more than a few simple characters, so we move on to larger storage units.
A Kilobyte (abbreviated as KB) is a set of 1024 bytes, although it is also simplified in common language as referring to 1,000 bytes.
Since the beginning of microcomputers (hey, not computing, but microcomputers), the KB has been the most frequently talked about unit. However, it should be noted that many of the first microcomputers did not have storage units by default, they had to be installed externally afterwards.
The first floppy drives had between 100 and 400 KB of capacity per disk, even going over 700 KB before moving on to the higher storage unit, which I will talk about a little later.
RAM memory is also measured by the same parameters, since it uses bits to temporarily store information. For example, the first microcomputers integrated 1 KB of RAM, like the Sinclair ZX81, or a few more, like the 4 KB of the 1976 Apple I (yes, before the Sinclair model).
The megabyte (MB) consists of a set of 1024 KB or, for simplicity, we round it up to 1,000 KB.
The first hard drives, large-capacity storage units, ranged from one to ten megabytes at most.
To give you an idea, the first hard drive that I mounted in my first PC had 20 MB of capacity, much less than what a pendrive USB of the smallest.
Also, and "affectionately", the Megabyte is called "mega".
With the Gigabyte (GB), the computational way is repeated: 1 GB is 1024 MB (1,000 for short)
Like the "mega", the Gigabyte is known in the family as "giga", and it is a measure that we have much more in our mouths because, currently, most microcomputer systems measure their amounts of RAM and their memory devices. storage in "gigas".
For example, if we have to buy a new computer, we can value acquiring it with 2, 4, 8 or 16 GB of RAM, and with a disk that goes from 500 GB upwards.
The unit that passes the Gigabyte is the Terabyte (TB). And, as we could already imagine, 1 TB equals 1024 GB (yes, for simplicity, we will refer to 1,000 GB).
At the moment, we are talking about Terabytes for the most powerful hard drives and storage units, as well as for the information downloaded and exchanged in networks of all kinds, the Internet of course.
From here on, the names of the following storage measures are less heard, since their size is such that, until now, they are only used in more technical conversations, such as those referring to the Big data, so I'll simplify them with a schematic:
1 Petabyte (PB) = 1024 Terabytes
1 Exabyte (EB) = 1024 Petabytes
1 Zettabyte (ZB) = 1024 Exabytes
1 Yottabyte (YB) = 1024 Zettabytes
What, logically, comes from here exceeding the Yottabyte, has not yet been standardized, that is, there is no universally accepted nomenclature to refer to such a volume of data.
This is so because, simply, it has not yet been necessary to name the units that come beyond the Yottabyte. Simply put, humanity has not generated enough information to handle these figures.