One of the major points of confusion for people new to computers is the difference between bits and bytes. This difference usually becomes important for the general user when discussing download speeds on the internet.
Bits are the basic unit of in the digital world. A single bit can only take on two values, either 0 or 1. The whole digital world is based on this binary situation.
When talking about file size or transfer rates, bits are always represented using a lower case 'b'. For example:
Bytes (also know as octets) are a combination of eight (8) bits.
When talking about file size or transfer rates, bytes should always be represented by an upper case 'B'. For example:
To confuse things a little further, in the computer world, the prefix kilo doesn't actually mean 1000 as it does in the rest of the world (e.g. 1000 metres = 1 kilometre). In the computer world one kilobyte (kB) is actually 1024 bytes (B).
This is a list of common sizes, their abbreviations and equalities:
When discussing this topic on internet forums like TechTalk there is often confusion about whether we are talking about bits (b) or bytes (B). Even experienced and knowledgable people often accidentally use a lower case 'b' where they should have used an upper case 'B' and vice versa.
Typically, modem speeds and speeds provided by ISPs are quoted in kilobits per second (bps). For example someone may have a 1.5Mb (or 1500kb) ADSL connection which actually means 1.5 megabits per second.
On the other hand, transfer speeds are typically quoted in kilobytes (kB/s) or megabytes (MB/s). For example someone may be downloading at 100kB/s.
It is important to keep all these things in mind when discussing topics such as file size and transfer rates.