It is possible to distinguish developers by sector, those skilled in the software business, and those specialized in the web, and the sectors of information and communications technology that matters to it two-thirds of developers sectoral activities.
A developer needs to know several languages but ...
For the hardcore development, it is often good to know a statically typed language and low level like C or C ++, in tandem with a "script" language like Python, Ruby or Perl. Where the first is strong and will serve coding the heart of programs, the second allows you to work these pieces of code together, writing tests and all the ancillary code of a project, very quickly. This kind of tandem languages (and sometimes wise choice to use one or the other for that part of the project) can efficiently produce quality code. For the web, you must often use a "business" language, which is the server side work, and a scripting language that will run in the browser.
Knowing bottom 3 languages, that's a lot. Knowing perfectly see 1 see 2 programming languages (more tools), this is what most developers make.
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