Resolution

ADC:

The resolution of an ADC is the range of values that you can map your range of voltages onto. A higher resolution grants a higher accuracy of voltage measuring (or mathematically a decrease in $\Delta Y$ inaccuracy)

ADC Resolution:

The resolution of an ADC system is determined by the number of voltage divisions, where the amount of these divisions is:

$$N=2^M$$

Where M is the ADC's resolution in amount of bits

Voltage Resolution:

The Voltage Resolution is related to the digital resolution through:

$$V_{res}=\frac{\Delta V}{2^M}=\frac{V_{max}-V_{min}}{2^M}$$

Dynamic Range:

Another way to characterize our ADC is Dynamic Range:

$$DynamicRange(dB)=20{\log }_{10}[\frac{V_{max}}{V_{res}}]$$

Fundamentally we are able to define our Least Significant Bit voltage as our $V_{res}$ to save confusion.

ENOB:

However, as we are no longer only dealing with Ideal Systems, we also have to take into account electrical noise, giving us something called Effective Number of Bits (ENOB):

$$ENOB=\frac{S/N-1.76}{6.02}$$

Its to be noted that $1.76\approx 10lo{g}_{10}(\frac{3}{2})$ which represents our quantisation error and $6.02\approx 20lo{g}_{10}(2)$ which converts decibels to bits. Another note is that for varying signals in ADCs we take S to be the MEAN voltage, using RMS