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PHPStorm IDE is a useful addition to the toolbox of any webdeveloper. It works great in combination with similar IDEs for Ruby (RubyMine), Python (PyCharm), NodeJS (Webstorm/PHPStorm), Go (Goland), and Java (IntelliJ).
Students and teachers are eligible to use all JetBrains tools free.
SpecsUpdate
Pros
Pro Cross-platform
Can work on your application on the 3 major OSs - Linux, macOS, Windows. This is the upside of using Java.
Pro Intelligent code completion
PhpStorm has two types of autocompletion: structural completion and word expansion.
Structural autocompletion makes predictions based on its understanding of PHP, while the latter tries to predict the word currently being typed based on previously typed words. Word expansion also works in comments and docstrings and it's similar to vim's omnicompletion.
Both types of autocompletion work extremely well, have little to no problems and are quite fast even when loading suggestions on the go.
Pro Outstanding JavaScript Development capabilities
Gives superior support when developing JavaScript, TypeScript, CoffeeScript code with code completion, linting, debugging, refactoring, etc.
Pro Can upgrade to IntelliJ for full language stack
If you are a Polygot or if you mainly write code in Ruby, Python, Go, (or some other) plugins, you can get one piece of software and can do Backend/Frontend in the same IDE while being full featured and all pretty similar. Jetbrains IDEs work all based on a plugin model, although there are exceptions (You can't just get WebStorm and install Ruby/Python, but can install everything on IntelliJ).
Pro Comes with the ability to test RESTful Web Services
You can save time on building your own or integrating libraries for testing RESTful Web Services. PHPStorm enables you to test endpoints without leaving your workspace or disrupting your workflow. You can code your endpoints in one window and test it immediately in another window.
Pro It comes with Testing RESTful Web Services
Save time of building your own or integrating libraries for testing RESTful Web Services. PHPStorm enables you to test endpoints without leaving your workspace or disrupting your workflow . You can code your endpoints in one window and test it immediately from another window.
Cons
Con Uses a lot of memory
Can use a lot of memory and need to be restarted. This has been improving, but it still apparent.
Con Cost - commercial software
If you subscribe you can get the full license even after canceling, but it's still commercial software and this is it's main disadvantage. WebStorm can be used if you don't need Database or PHP Support, which is another Jetbrains Product.
Con Resource exhaustive
It often maxes out even 4 cores, not to mention several hundred MBs of RSS with a single small project opened.