(Arduino) Using the Arduino IDE and the ESP826 NodeMCU board, this project demonstrates how to obtain the epoch time or the unix time. Obtaining the time of the epoch can be helpful for a variety of applications, including timestamping your readings, providing files with names that are distinct, and more. Because we will be requesting the current epoch time from an NTP server, the ESP8266 board really has to be connected to the internet. What is epoch time? The number of seconds that have transpired since the Unix epoch, which occurred at 00:00:00 Coordinated Universal Time (UTC) on January 1, 1970, minus any leap seconds, is referred to as the Epoch time or the UNIX time. It monitors the passage of time in seconds and does all calculations beginning at the same instant in time regardless of the time zone. It is frequently utilized in a variety of file formats and operating system configurations.

What is the purpose of the epoch time in Unix? Unix time is represented by a single signed number that increases by one every second. Because of this, it is far simpler for computers to both store and operate than other date systems. After that, interpreter programmes can turn information into a format that is readable by humans. The time 00:00:00 Coordinated Universal Time (UTC) on January 1, 1970 is the Unix epoch. Why is it necessary for us to use epoch time? In order for the computer to keep track of the time, it has to know when to begin. When computers keep track of time, one common standard they use is called the Epoch time. The time from the Epoch, which is measured in seconds, begins at 00:00:00 on Thursday, January 1, 1970 UTC. Therefore, the number of seconds that have passed since Epoch zero is the Epoch time.NTP (Network Time Protocol) (Network Time Protocol)

Network Time Protocol is a networking protocol that allows computer systems to synchronize their clocks with one another. NTP is an abbreviation for "Network Time Protocol." In other words, it is utilized to synchronize the clock times of computers that are connected to a network. NTP is a protocol that is commonly utilized to synchronize the clocks on many computers to a reference network. It synchronizes the epoch time of all networked devices to the Coordinated Universal Time (UTC) with an accuracy of around 50 milliseconds over the wide-area network (WAN) and less than 5 milliseconds over the local area network (LAN). In order to retrieve epoch time from an ESP8266 NodeMCU connected to an NTP server, the server will function according to the client-server model. We will make use of the NTP server located at pool.ntp.org, which is readily available to people all over the world. As the client, our ESP8266 NodeMCU development board will connect to the NTP server over UDP on port 123. This connection will take place on our behalf. The server, which is located at pool.ntp.org, will be able to connect with the client by using this port. When the connection has been successfully established, the ESP8266 NodeMCU board will then submit a request to the server. After the NTP has been given the request, it will send out a time stamp that includes all of the relevant information regarding the time. Bringing in the NTP Client and the Wi-Fi Libraries In order to retrieve the time at the current epoch using ESP8266, we will be including the following three libraries. Because we want our ESP8266 board to connect with the local network, we need to make sure that we have the ESP8266WiFi.h library. Because of this, we will have access to the NTP server via the internet, making this library an absolute necessity. Second, the

NTPClient.h library will take care of the synchronization of the NTP server, which is necessary in order to retrieve the current time from the NTP server.