Web applications that directly runs in the browser Backend is server side application and database Frontend is client side aplication
HTTP is hypertext transfer protocol which is used to load pages by using hypertext links. Node js has built in module http, which creates the http server to take request of client and give response back to client
Role of url in http is specifies the address which contains the information of required data.
Promise is object,It is eventuall completion or failure of asynchronous operations.
.catch()-to handle errors in promises .finally()-executes if promise is resolved or rejected
The control of code looses if code accessed by third party api's or looses control of callback to main function.
promises and sync await
it returns undefined
user,groups,other
syntax errors-if we not follow the rules type errors - redeclaring of const variable gives type errors reference errors-trying to access before declaring
| curl -o "harrypotter-gobletoffire.txt" https://raw.githubusercontent.com/bobdeng/owlreader/master/ERead/assets/books/Harry%20Potter%20and%20the%20Goblet%20of%20Fire.txt | |
| #to take the url of file given and storing as text file using curl -o | |
| head -n 3 harrypotter-gobletoffire.txt | |
| #to get first lines of code we use head command | |
| head -n 5 | |
| #harrypotter-gobletoffire.txt | |
| tail -n 10 harrypotter-gobletoffire.txt |
| #Structure of drill creation. | |
| pwd | |
| #it is to check at present in which directory we are. | |
| mkdir hello | |
| #To create directory | |
| cd hello | |
| #cd means change directory ,here to create subdirectories and files we are going to hello. |