1
00:00:02,250 --> 00:00:04,680
So what is a third-party library,

2
00:00:04,680 --> 00:00:07,170
that's of course very important to understand.

3
00:00:07,230 --> 00:00:14,010
We're working with Javascript and by the way for the concept of third-party libraries, it absolutely

4
00:00:14,010 --> 00:00:21,180
does not matter if you're working with Javascript in the browser or with Node.js which would allow

5
00:00:21,180 --> 00:00:24,620
you to write server side applications with Javascript.

6
00:00:24,660 --> 00:00:31,020
Actually the programming language doesn't even matter because that idea of having third-party libraries

7
00:00:31,230 --> 00:00:34,230
does not just exist in Javascript world,

8
00:00:34,230 --> 00:00:40,650
it's available for any programming language out there because the idea is the following; you are writing

9
00:00:40,650 --> 00:00:44,100
code for your application, that's your job as a developer.

10
00:00:44,100 --> 00:00:50,630
Now when writing this code, there are certain problems you have to solve. In this dummy application here,

11
00:00:50,640 --> 00:00:54,840
we're building a two array function which combines two numbers into an array

12
00:00:54,840 --> 00:01:00,900
but then let's say we also want to get the difference between this array and some other array, which

13
00:01:00,930 --> 00:01:02,470
I hardcoded in there.

14
00:01:02,470 --> 00:01:10,530
Now that's just one example of course but it's typical for tasks or for problems you will face as

15
00:01:10,530 --> 00:01:15,110
a developer. You're working on some project and for that, you need to write a lot of code.

16
00:01:15,120 --> 00:01:21,300
Now some of that code is really specific to that project, really specific to the business logic behind

17
00:01:21,300 --> 00:01:22,620
that project

18
00:01:22,620 --> 00:01:29,940
but other functionalities which you might need as part of this project might be more like this type of

19
00:01:29,940 --> 00:01:30,720
problem here,

20
00:01:30,780 --> 00:01:36,900
you might need some utility function because maybe as part of the business logic of your project, you

21
00:01:36,900 --> 00:01:39,210
need to get the difference between two arrays,

22
00:01:39,300 --> 00:01:45,420
let's say two lists of customers but the comparison itself of the two arrays,

23
00:01:45,420 --> 00:01:48,760
that's a problem that's not specific to your project,

24
00:01:48,930 --> 00:01:55,680
that's a utility function you have to write and therefore you have to spend time and energy on a task

25
00:01:56,100 --> 00:01:59,050
which is not directly related to your project,

26
00:01:59,050 --> 00:02:05,160
now that's where third-party libraries come in. Third-party libraries are essentially packages of code,

27
00:02:05,310 --> 00:02:12,180
typically packages of functions written in Javascript which have all that logic in them

28
00:02:12,180 --> 00:02:19,470
so that you can just reach out to these predefined, prewritten functions and functionalities and use

29
00:02:19,470 --> 00:02:21,360
them in your project.

30
00:02:21,420 --> 00:02:29,040
So third-party libraries are really all about adding utility functions of different complexities, can

31
00:02:29,040 --> 00:02:35,160
be very simple, very trivial utility functions or more complex functionalities which you want to add, that

32
00:02:35,160 --> 00:02:36,330
doesn't really matter.

33
00:02:36,330 --> 00:02:42,810
The idea is that third-party libraries can help you have an easier life as a developer because they

34
00:02:42,810 --> 00:02:48,630
take away some of the complexity which is not directly related to your core project, to your core business

35
00:02:48,630 --> 00:02:51,140
logic which you still might need.

36
00:02:51,150 --> 00:02:52,770
So let's have a look at some examples.