This week in class was all about Binary. So what is Binary. Well its a numerical system used by Computer and Electronics to understand. Instead of the normal number system of Base 10 that we used everyday, Binary is a Base 2 system. This makes it easier for electronics because they have circuits that are either on or off. Binary only uses two different numbers, either “1” being on, or “0” being off.
A particularly handy size chunk of computer memory happens to be 8 bits long. This size chunk of memory can be used to represent any number from zero (00000000) to 255 (11111111). Why does 11111111 (base 2) equal 255? Because it means:
1 x 128 + 1 x 64 + 1 x 32 + 1 x 16 +
1 x 8 + 1 x 4 + 1 x 2 + 1 x 1 = 255
A better way to get a look at how to compute binary number with ones and zeros it to make a chart like this:
We have a special name for a chunk of memory that is 8 bits long: it is called a byte. This is the basic unit we use to measure computer memory size. The 8 bit standard is used because its the smallest base power of 2 that can also represent letters in the English Language. Although we didn’t cover much on how computer compute letters from ones and zeros, we did discuss how computers use Binary to compute IP addresses. Something that I found interesting this week that answered a question I always wondered was why Router Subnet Mask always started with 255.255. and when you look at binary how the 8 bit long base 2 numbers all add up to 255 it finally made sense.
This week I contributed to Diigo a link on a Binary Game by Cisco http://forums.cisco.com/CertCom/game/binary_game_page.htm
This game is actually kinda fun and I got faster and faster as I did it. I found on the larger numbers to compute it was easier to just subtract from 255. Like to compute 247 for instance: 255 – 247=8, so it was easier to know if all ones=11111111=255, then 247 would equal all ones except a 0 in the Eights place= 11110111.