I always thought that capitals were used for multiplying prefixes and lower case for divider prefixes. i have had this problem before being assured that it's lower case for kbps but i don't get it because no one uses mbps do they? T, G, M, K, unit, m, µ, n, p, Am I missing something here?
Yes, you are missing something. There are a set of prefixes used for SI (
Système international d'unités or International system of units), which are standardized for use within this system. You have (T)era, (G)iga, (M)ega, (k)ilo, m(illi), (μ)icro, (n)ano, (p)ico, etc. (Notice how they ran out of m's and had to switch to Greek?)
This set of prefixes are used for quoting physical measurements in the SI (metric) system.
Other prefixes are used in other contexts. For example, in U.S. customary usage, M often means 1000, and MM means one million. So, for example, 1 MMbbl/d is one million barrels per day, and 1 MMscf/h is one million standard cubic feet per hour.
Therefore, we can question whether "bits" in computing are part of the SI system, and should use SI prefixes. Clearly there are other historical conventions with other usages. Since computing uses powers of two (for good reasons), the convention since the beginning has been that in computing the "K" and "M" prefixes are powers of two, namely 2
10 and 2
20.
According to which culture and convention one is working with, "M" could mean 1 000 000 , 1000, or 1024.