1
00:00:06,577 --> 00:00:09,114
- [Instructor] So as we've
discussed, a web server would

2
00:00:09,114 --> 00:00:12,130
normally have a front-end web server

3
00:00:12,130 --> 00:00:14,898
and a back-end database server.

4
00:00:14,898 --> 00:00:18,285
Sometimes, this is all
part of the same machine.

5
00:00:18,285 --> 00:00:22,014
Web application request is
sent from the client's browser

6
00:00:22,014 --> 00:00:23,603
to the web server.

7
00:00:23,603 --> 00:00:27,036
From there, the web server
will reach back to the database

8
00:00:27,036 --> 00:00:31,835
server for content to return
to the client's browser.

9
00:00:31,835 --> 00:00:34,435
The response from the web
server is sent back to the

10
00:00:34,435 --> 00:00:37,024
client's browser and then rendered

11
00:00:37,024 --> 00:00:39,191
in the browser's software.

12
00:00:41,963 --> 00:00:44,767
With the web service, the
web server and database

13
00:00:44,767 --> 00:00:46,887
work together in the same way.

14
00:00:46,887 --> 00:00:50,735
The main difference is that
the data returned to the client

15
00:00:50,735 --> 00:00:53,914
is not rendered in the browser.

16
00:00:53,914 --> 00:00:57,664
A web service request
is sent from the client

17
00:00:57,664 --> 00:00:59,635
to the web service.

18
00:00:59,635 --> 00:01:02,667
This request is normally in the form of

19
00:01:02,667 --> 00:01:04,971
soap or rest.

20
00:01:04,971 --> 00:01:08,784
The web service then responds
with data in the form of

21
00:01:08,784 --> 00:01:10,451
XML or JSON.

22
00:01:11,550 --> 00:01:16,103
It's then up to the client
application to consume that data

23
00:01:16,103 --> 00:01:18,790
and display it to the user.

24
00:01:18,790 --> 00:01:22,241
This is very common
with mobile applications

25
00:01:22,241 --> 00:01:27,145
where the mobile application
speaks to the web service

26
00:01:27,145 --> 00:01:30,562
in the form of soap or, many times, rest,

27
00:01:31,570 --> 00:01:35,686
and the web service responds
to the mobile application

28
00:01:35,686 --> 00:01:38,436
in the form of XML or JSON

29
00:01:39,677 --> 00:01:44,661
and the data that you see
rendered in the mobile application

30
00:01:44,661 --> 00:01:47,559
is what was returned from the web service.

31
00:01:47,559 --> 00:01:50,442
It can also be used in
desktop applications

32
00:01:50,442 --> 00:01:53,913
as well as server-to-server
communications.