i did not understand about binary coding

if you think of this binary code: 0001

it is basically start from the right side: starting with that 1: 0001 <- this

Every time that right hand side number represents a 1, so from then on moving to the left your are basically timsing by 2, so start with 1 then you move left and you do 1 times 2 which is 2 so that second column on the right value wise is 2. You repeat you times that column by 2, 2 times 2 = 4. You move again to the left and times that column value by 2 which would be 4 times 2 = 8. so now you know that this: 0000 is just placeholder values for the numbers 1,2,4 and 8 but starting with 1 from the right side so you read it like 8,4,2 and 1 which is what the 0000 is representing. So if we have 0001: and we want to know what that 1 means it is basically saying ok in my placeholders which are 8,4,2,1 my 1 placeholder has a 1 now not a zero meaning i have 1 in my 1 column so the answer would be 1. If i were to say ok whats this value: 0111

I would do ok so i have a 1 in my 1 column so so far my sum is 1, i have a 1 in my 2 column meaning i have a 2 so the sum so far is 3 because i have 1 in my 1 column and 1 in my 2 column. Remember we are not adding these 1's we are adding the values that these 1's represent like the 8,4,2,1 numbers. Last we have a 1 in the 4 column so the sum here is the 4 + 2 + 1 = 7.

Which part didn't you understand?

I don't know if that helped or if you already figured it out but you're welcome :)