What is Node js?
NodeJS
is an open source, cross platform java Script run time
environment used to develop server side java Script based applications. Nodejs
can be used to develop a fullStack (both back end and front end) in same
language. It was Developed by Ryan Dahl. NodeJS comes with
several JavaScript libraries that help basic programming.Node JS is most
suitable for data-intensive real time applications(i.e it is ideal for I/O
heavy applications).But this is not suitable for CPU intensive applications.It
is single threaded and uses non-blocking I/O model.(i.e Node js handles
multiple i/o requests asynchronously using the event-loop)
Node
JS eco-system ‘npm’ is the largest in the world for open source libraries.
What
is NPM?
It
is the Node Package Manager. Node.js has an npm registry ,which has a lot of
packages. It will check the online repositories for node js modules
and install them to Node js.It will further do version mangement and dependancy
management of the installed packages.By default all the dependencies will get
installed to ‘node_modules’ directory.These moules can be installed globally or
locally.By default, NPM installs any dependency in the local scope.Global
installations will be available throughout the system while local installations
will only be available for that particular application.
Package.json
package.json
is present in the root directory of any Node application/module.It define s the
properties of a package. package.json’ will contain name, version, author,
repository, required node version, scripts and dependencies etc
