Yes. We normally count in 'base 10', which means each digit can go from 0 to 9 as we count up, then the digit to its left increases by one. The rightmost position is the units, the next the tens (because we use base 10), the next hundreds (or 10 times 10), and so on, with each position worth 10 times the one to its right. So the number 12 means you have 2 units plus 1 ten. 123 means 3 units, 2 tens, and 1 hundred.

Binary is 'base 2', so as we count up each digit can only go from 0 to 1 before incrementing the position to its left, and each position is worth 2 times the one to its right. So 1 still means one, but 10 is 0 units plus 1 two, and 100 is 0 units, 0 tens and 1 four, totalling 4.