1. ## 010010101(help!)0101010100010101

Greetings:

Listen, Iv'e been trying to learn about binary numbers. The problem is, just when I THINK I have the concept down.... I don't. I know the whoal thing about hex numbers, but I just can't GET binary numbers. Please, someone write a tutorial, as simply as possible, about binary numbers.

P.S. = I know the thing about 0x in hex numbers being like a substitute for subscripts, but, what's with that? Why just 0x, what number is it representing?

2. To avoid confusing hex with ordinary numbers, they are sometimes written preceded by a zero and an "x" ("0x", a convention borrowed from the C programming language). Thus 0x100000 is a way to make sure that the value is one megabyte and not one hundred thousand.
From here http://www.yale.edu/pclt/BOOT/HEXNOTAT.HTM

For the tuts, do a search here on AO or google and you'll find more than you need.

3. just take your binary to hex and dont worry about it

break binary down into 4 place chunks and the conversion is easy ie

1001110101 would be 0010 1110 0101 then each group of 4 is one hex digit so this would be
0010 = 2 1110 = D 0101 = 5 so 1001110101 = 2D5. you can do the same thing for OCT with groups of three

4. ## 0x

Also sometime the x (if it is subscript, as number typed below the line, kind of hanging like a 2 in H2O) can mean the base of a number so you know if it's binary which is base 2, hexadecimal which is base 16 or Decimal which is base 10, Octal base 8 etc.. So in a lab you don't confuse numbers, like 11 with a subscript of 2 which would be a binary 3 value versus a value of 11 with a subscript of 10. Two VERY different values. The sub. lets you know what numbering system you are on and in turn gives you the intended value.

5. Ok, I've read the other comments and they sound confusing to me and I already know how to do it all. No offense to anyone but lets make it simplier. Ok, now think of it like this:
The first number in binary on the right(or the end of the number) is assigned the value of 1. Then the space left of it is two. The one left to that one is four. Every time the value doubles. So you go 1, 2, 4, 8, 16, 32, 64, 128, etc., etc. Like this:

0 0 0 0 0 0 0 0
128 64 32 16 8 4 2 1

Ok? So let's say you have a number of 100010101: You would translate it to decimal like this:

1 0 0 0 1 0 1 0 1
256 128 64 32 16 8 4 2 1

So you add up all the numbers that have a 1 above it, 256+16+4+1=277 in decimal.

And to do it in reverse all you have to do is pick the highest number assignment that is not more than the decimal number, then take what is left over and pick the highest number assignment that is not more than the leftover amount like this:

Let's say you have a number of 58. To change it to decimal you pick the highest number assignment not more than 58, which would be the space above 32.

1 0 0 0 0 0
32 16 8 4 2 1

Ok, so now you subtract 32 from 58 and you have 26 left. So what is the highest number above, that is not more than 26?

You got it.

1 1 0 0 0 0
32 16 8 4 2 1

So then you subtract 16 from 26 and you have 10 left over. So then you put

1 1 1 0 0 0
32 16 8 4 2 1

Ok so now you have 2 left over, so you leave the space above 4 0 and then add the last:

1 1 1 0 1 0
32 16 8 4 2 1

So in binary 111010 = 58 in decimal.

Hope this helps.
Watcher