How many bits can an Arduino uno read?
What is the maximum of bits that an Arduino can read on the digital input, which model in the Arduino range can read the most bits?


A digital input is by nature binary (i.e. a single bit). The answer to your question is therefore one bit per digital input. 

The total number of digital inputs depends on the board. It ranges from Arduino Micro (which has fewest less with than 10) to Arduino Mega which has the most with more than 60). 

Another possible interpretation of your question is the resolution of an analog pin (ADC). The AVR has max 10 bit resolution.

Cheers!