In Node.js you use JavaScript and that is why it's so popular. You don't have to learn a new language, just code like you do for web. If you already know JS go for it.

These days I would recommend going with Go. It's fast, nice, has a rich standard library and you compile to multiple platform with a single command.

This was answered pretty concisely on HackerNews recently when a developer talked about going back to PHP for server side ops:

Today my language usage looks like this:

• Web services / APIs: Node.js [1]

• Front-ends that require easily modifiable templates and quick command line scripts: PHP [2]

• When I need speed and low latency for a network connected app: Go [3]

• When I need speed on an app that requires no network: C

[1] The promise chain asynchronous nature of Node.js makes it great for web services in my opinion. And the ability to easily have global variables that persist across connections for things like caching and pooling is a huge plus over PHP.

[2] PHP is very good at spitting out HTML and making web service requests, the performance is acceptable in most cases, and it is really easy for most people to edit, even people without a CS background. Likewise, for quick command like scripts PHP is unbeatable in my opinion. The tools it provides out of the box means most common command line tasks can be done 100% with the standard library. No package manager required. Though if you need to add packages PHP is pretty good about that now. Incidentally the fact the standard lib does so much is also one of PHP weaknesses. The standard library is a mess of inconsistently named functions and classes that grew organically over 20 years.

[3] I've saturated my loopback network interface on a non-trivial app on my Macbook Pro using Go. PHP and node don't even come remotely close.

[via HN]