Would you like to inspect the original subtitles? These are the user uploaded subtitles that are being translated:
1
00:00:10,900 --> 00:00:16,370
Remember from the earlier video that a byte can store only zeros and ones.
2
00:00:16,370 --> 00:00:19,775
That means we can have 256 possible values.
3
00:00:19,775 --> 00:00:21,020
By the end of this video,
4
00:00:21,020 --> 00:00:24,215
you'll learn how we can represent the words, numbers,
5
00:00:24,215 --> 00:00:26,490
emojis and more we see on our screens,
6
00:00:26,490 --> 00:00:30,015
from only these 256 possible values.
7
00:00:30,015 --> 00:00:32,195
It's all thanks to character encoding.
8
00:00:32,195 --> 00:00:34,310
Character encoding is used to assign
9
00:00:34,310 --> 00:00:38,200
our binary values to characters so that we as humans can read them.
10
00:00:38,200 --> 00:00:41,060
We definitely wouldn't want to see all the text in our emails and
11
00:00:41,060 --> 00:00:45,130
Web pages rendered in complex sequences of zeros and ones.
12
00:00:45,130 --> 00:00:47,620
This is where character encodings come in handy.
13
00:00:47,620 --> 00:00:50,415
You can think of character encoding as a dictionary.
14
00:00:50,415 --> 00:00:52,490
It's a way for your computers to look up
15
00:00:52,490 --> 00:00:56,420
which human characters should be represented by a given binary value.
16
00:00:56,420 --> 00:00:59,650
The oldest character encoding standard used this ASCII.
17
00:00:59,650 --> 00:01:01,550
It represents the English alphabet,
18
00:01:01,550 --> 00:01:03,605
digits, and punctuation marks.
19
00:01:03,605 --> 00:01:07,730
The first character in ASCII to binary table, a lowercase a,
20
00:01:07,730 --> 00:01:13,250
maps to 0 1 1 0 0 0 0 1 in binary.
21
00:01:13,250 --> 00:01:15,330
This is done for all the characters you can find in
22
00:01:15,330 --> 00:01:19,245
the English alphabet as well as numbers and some special symbols.
23
00:01:19,245 --> 00:01:22,190
The great thing with ASCII was that we only needed to use
24
00:01:22,190 --> 00:01:26,350
127 values out of our possible 256.
25
00:01:26,350 --> 00:01:28,100
It lasted for a very long time,
26
00:01:28,100 --> 00:01:29,900
but eventually it wasn't enough.
27
00:01:29,900 --> 00:01:33,650
Other character encoding standards recreated to represent different languages,
28
00:01:33,650 --> 00:01:36,350
different amounts of characters and more.
29
00:01:36,350 --> 00:01:40,875
Eventually they would require more than 256 values we were allowed to have.
30
00:01:40,875 --> 00:01:42,635
Then came UTF 8.
31
00:01:42,635 --> 00:01:45,185
The most prevalent encoding standard used today.
32
00:01:45,185 --> 00:01:47,440
Along with having the same ASCII table,
33
00:01:47,440 --> 00:01:50,435
it also lets us use a variable number of bytes.
34
00:01:50,435 --> 00:01:53,140
What do I mean by that? Think of any emoji.
35
00:01:53,140 --> 00:01:55,770
It's not possible to make emojis with a single byte,
36
00:01:55,770 --> 00:01:58,505
so as we can only store one character in a byte,
37
00:01:58,505 --> 00:02:02,910
instead UTF 8 allows us to store a character in more than one byte,
38
00:02:02,910 --> 00:02:05,240
which means endless emoji fun.
39
00:02:05,240 --> 00:02:08,060
UTF 8 is built off the Unicode Standard.
40
00:02:08,060 --> 00:02:09,650
We won't go into much of detail,
41
00:02:09,650 --> 00:02:14,780
but the Unicode Standard helps us represent character encoding in a consistent manner.
42
00:02:14,780 --> 00:02:17,420
Now that we've been able to represent letters, numbers,
43
00:02:17,420 --> 00:02:19,480
punctuation marks and even emojis,
44
00:02:19,480 --> 00:02:21,170
how do we represent color?
45
00:02:21,170 --> 00:02:22,985
Well, there are all kinds of color models.
46
00:02:22,985 --> 00:02:26,355
For now, let's stick to a basic one that's used in a lot of computers.
47
00:02:26,355 --> 00:02:29,270
RGB or red, green, and blue model.
48
00:02:29,270 --> 00:02:30,781
Just like the actual colors,
49
00:02:30,781 --> 00:02:32,690
if you mix a combination of any of these,
50
00:02:32,690 --> 00:02:35,240
you'll be able to get the full range of colors.
51
00:02:35,240 --> 00:02:39,855
In computerland, we use 3 characters for the RGB model.
52
00:02:39,855 --> 00:02:42,320
Each character represents a shade of the color and
53
00:02:42,320 --> 00:02:45,350
that then changes the color of the pixel you see on your screen.
54
00:02:45,350 --> 00:02:48,485
With just eight combinations of zeros and ones,
55
00:02:48,485 --> 00:02:51,665
were able to represent everything that you see on your computer,
56
00:02:51,665 --> 00:02:53,245
from a simple letter a,
57
00:02:53,245 --> 00:02:57,225
to the very video that you're watching right now on the Coursera website.
58
00:02:57,225 --> 00:02:59,630
Very cool. In the next video,
59
00:02:59,630 --> 00:03:03,990
we'll discuss how we actually generate the zeros and ones.
5099
Can't find what you're looking for?
Get subtitles in any language from opensubtitles.com, and translate them here.
Afrikaans
Albanian
Amharic
Arabic
Armenian
Azerbaijani
Basque
Belarusian
Bengali
Bosnian
Bulgarian
Catalan
Cebuano
Chichewa
Chinese (Simplified)
Chinese (Traditional)
Corsican
Croatian
Czech
Danish
Dutch
English
Esperanto
Estonian
Finnish
French
Frisian
Galician
Georgian
German
Greek
Gujarati
Haitian Creole
Hawaiian
Hungarian
Icelandic
Indonesian
Irish
Italian
Japanese
Kazakh
Khmer
Korean
Kurdish (Kurmanji)
Kyrgyz
Lao
Latvian
Lithuanian
Luxembourgish
Macedonian
Malagasy
Malay
Maltese
Maori
Mongolian
Myanmar (Burmese)
Nepali
Norwegian
Pashto
Polish
Portuguese
Romanian
Russian
Samoan
Serbian
Sesotho
Shona
Sinhala
Slovak
Slovenian
Somali
Spanish
Swahili
Swedish
Tajik
Thai
Turkish
Ukrainian
Urdu
Uzbek
Vietnamese