It's pretty much a similar stack of components as LAMP, except the Apache is being replaced by Nginx. Pronounced “engine-x”, which explain the Eon “LEMP”, Nginx is an HTTP proxy application with reputably much smaller footprints compared to Apache, allowing it to handle a higher load of HTTP requests.
LAMP - > Linux Apache MySQL PHP
LEMP - > Linux Nginx(Engine-X) ,MySQL,PHP
In LEMP, Nginx replaces Apache, even though Apache is highly used web server software, but Nginx is more efficient in static content service than Apache. Nginx will give you better performance for large amounts of traffic. Nginx is faster and able to handle a much higher load compared to Apache using the same set of hardware.
The major benefit to configure LAMP stack is that it has a number of modules, which gives more functionality compared to Nginx oin LEMP.
Apache is more commonly used, especially in a shared hosting environment, however can cause heavy ram usage if not configured.
Both the web servers operate differently, and require different configurations to set them up. Your requirements on which one to use will depend on the application you wish to run on the server.
Apart from this, it is also possible to configure Nginx+Apache in reverse proxy mode to handle the load as well as traffic effectively. Here Nginx will server static contents and the dynamic requests will be handled by Apache.