What does this boolean “(number & 1) == 0” mean?

Question

On CodeReview I posted a working piece of code and asked for tips to improve it. One I got was to use a boolean method to check if an ArrayList had an even number of indices

Answer 1

It is performing a binary and against 1, which returns 0 if the least significant bit is not set

for your example

00001010 (10)

00000001 (1)

===========

00000000 (0)