An Application Programming Interface is a way for two or more computer programs to communicate with each other. It is a type of software interface, offering a service to other pieces of software. Each time you use an app like Facebook, send an instant message, or check the weather on your phone, you're using an API.
At some point or another, most large companies have built APIs for their customers, or for internal use.
There are also three common types of API architectures:
In the world of technology, there are vast numbers of users' communicating with different devices in different languages. That also includes many ways in which they transmit data along with the different software they implement. So, communicating worldwide will not be possible if there were no fixed 'standards' that will govern the way user communicates for data as well as the way our devices treat those data.
Protocols are set of rules that help in governing the way a particular technology will function for communication.In other words, it can be said that the protocols are digital languages implemented in the form of networking algorithms. There are different networks and network protocols, user's use while surfing.
There are various types of protocols. These are:
01- Transmission Control Protocol (TCP)
02- Internet Protocol (IP)
03- User Datagram Protocol (UDP)
04- Post office Protocol (POP)
05- Simple mail transport Protocol (SMTP)
06- File Transfer Protocol (FTP)
07- Hyper Text Transfer Protocol (HTTP)
08- Hyper Text Transfer Protocol Secure (HTTPS)
09- Telnet
10- Gopher
1- Transmission Control Protocol (TCP): TCP is a popular communication protocol which is used for communicating over a network. It divides any message into series of packets that are sent from source to destination and there it gets reassembled at the destination.
2- Internet Protocol (IP): IP is designed explicitly as addressing protocol. It is mostly used with TCP. The IP addresses in packets help in routing them through different nodes in a network until it reaches the destination system. TCP/IP is the most popular protocol connecting the networks.
3- User Datagram Protocol (UDP): UDP is a substitute communication protocol to Transmission Control Protocol implemented primarily for creating loss-tolerating and low-latency linking between different applications.
4- Post office Protocol (POP): POP3 is designed for receiving incoming E-mails.
5- Simple mail transport Protocol (SMTP): SMTP is designed to send and distribute outgoing E-Mail.
6- File Transfer Protocol (FTP): FTP allows users to transfer files from one machine to another. Types of files may include program files, multimedia files, text files, and documents, etc.
7- Hyper Text Transfer Protocol (HTTP): HTTP is designed for transferring a hypertext among two or more systems. HTML tags are used for creating links. These links may be in any form like text or images. HTTP is designed on Client-server principles which allow a client system for establishing a connection with the server machine for making a request. The server acknowledges the request initiated by the client and responds accordingly.
8- Hyper Text Transfer Protocol Secure (HTTPS): HTTPS is abbreviated as Hyper Text Transfer Protocol Secure is a standard protocol to secure the communication among two computers one using the browser and other fetching data from web server. HTTP is used for transferring data between the client browser (request) and the web server (response) in the hypertext format, same in case of HTTPS except that the transferring of data is done in an encrypted format. So it can be said that https thwart hackers from interpretation or modification of data throughout the transfer of packets.
9- Telnet: Telnet is a set of rules designed for connecting one system with another. The connecting process here is termed as remote login. The system which requests for connection is the local computer, and the system which accepts the connection is the remote computer.
10- Gopher: Gopher is a collection of rules implemented for searching, retrieving as well as displaying documents from isolated sites. Gopher also works on the client/server principle.
Some other popular protocols act as co-functioning protocols associated with these primary protocols for core functioning. These are:
Hypertext Transfer Protocol (usually abbreviated to HTTP) is a communications protocol. It is used to send and receive webpages and files on the internet. It was developed by Tim Berners-Lee and is now coordinated by the W3C. HTTP version 1.1 is the most common used version today. It is defined in RFC 2616.
About half of websites already use its successor HTTP/2 (which almost all web browsers support), and 25% of websites already support its much faster proposed successor HTTP/3, which is close to being standardized.
The secure variant of HTTP is called HTTPS (Hypertext Transfer Protocol Secure), and is used by more than 79% of websites,[1] such as payment websites (if it's not used, then it's a clear signal that the payment site is a scam).
HTTPS is used by default by most web browsers (even if not requested by the user), assuming the web server supports it. If browsing to a website, and the web browser shows it starting with http: without an s before the colon (or an unlocked icon is seen), then that website is not secure, then passwords or other data sent to them can be stolen. HTTPS encrypts all the information that is sent and received. This can stop malicious users such as hackers from stealing the information. HTTPS uses port 443 for communication instead of port 80.
HTTP works as such, a user agent, usually meaning the web browser, connects to a (web) server. A user agent could also be a web crawler, or so-called "spider", but most users do not use such tools (they are used be search engines, such as Google). The server must be located using a URL or URI. It normally connects to port 80 on a computer.
HTTPS is HTTP with encryption. The only difference between the two protocols is that HTTPS uses TLS (SSL) to encrypt normal HTTP requests and responses. As a result, HTTPS is far more secure than HTTP. A website that uses HTTP has http:// in its URL, while a website that uses HTTPS has https://.
Although HTTPS increases the security of the website, this does not mean that hackers cannot hack it; even after switching HTTP to HTTPS, your site may be attacked by hackers, so in addition, to be safe your website in this way, you need to pay attention to other points to be able to turn your site into a secure site.
HTTP response status codes indicate whether a specific HTTP request has been successfully completed.
Responses are grouped in five classes:
Status Code 200 – This is the standard “OK” status code for a successful HTTP request. The response that is returned is dependent on the request. For example, for a GET request, the response will be included in the message body. For a PUT/POST request, the response will include the resource that contains the result of the action.
Status Code 201 – This is the status code that confirms that the request was successful and, as a result, a new resource was created. Typically, this is the status code that is sent after a POST/PUT request.
Status Code 204 – This status code confirms that the server has fulfilled the request but does not need to return information. Examples of this status code include delete requests or if a request was sent via a form and the response should not cause the form to be refreshed or for a new page to load.
Status Code 304 – The is status code used for browser caching. If the response has not been modified, the client/user can continue to use the same response/cached version. For example, a browser can request if a resource has been modified since a specific time. If it hasn’t, the status code 304 is sent. If it has been modified, a status code 200 is sent, along with the resource.
Status Code 400 – The server cannot understand and process a request due to a client error. Missing data, domain validation, and invalid formatting are some examples that cause the status code 400 to be sent.
Status Code 401 – This status code request occurs when authentication is required but has failed or not been provided.
Status Code 403 – Very similar to status code 401, a status code 403 happens when a valid request was sent, but the server refuses to accept it. This happens if a client/user requires the necessary permission or they may need an account to access the resource. Unlike a status code 401, authentication will not apply here.
Status Code 404 – The most common status code the average user will see. A status code 404 occurs when the request is valid, but the resource cannot be found on the server. Even though these are grouped in the Client Errors “bucket,” they are often due to improper URL redirection.
Status Code 409 – A status code 409 is sent when a request conflicts with the current state of the resource. This is usually an issue with simultaneous updates, or versions, that conflict with one another.
Status Code 410 – Resource requested is no longer available and will not be available again. Learn about network error 410.
Status Code 500 – Another one of the more commonly seen status codes by users, the 500 series codes are similar to the 400 series codes in that they are true error codes. The status code 500 happens when the server cannot fulfill a request due to an unexpected issue. Web developers typically have to comb through the server logs to determine where the exact issue is coming from.
Encryption is the method by which information is converted into secret code that hides the information's true meaning. The science of encrypting and decrypting information is called cryptography.
In computing, unencrypted data is also known as plaintext, and encrypted data is called ciphertext.
The domain name system (DNS) is a naming database in which internet domain names are located and translated into Internet Protocol (IP) addresses. The domain name system maps the name people use to locate a website to the IP address that a computer uses to locate that website.
The Domain Name System is the hierarchical and decentralized naming system used to identify computers reachable through the Internet or other Internet Protocol networks. The resource records contained in the DNS associate domain names with other forms of information.
DNS translates human readable domain names (for example, www.amazon.com) to machine readable IP addresses (for example, 192.0. 2.44).