What to take into service for the frontend?

Question

css

LESS, Sass, SCSS, Stylus, Jade, Slim, Coffeescript, LiveScript, Haml, Markdown... A lot of things, but it's not entirely clear when and which of these is appropriate to use.
For example, what is suitable for:
1. Simple business card sites, landings.
2. Small online stores, catalog sites of small companies.
3. Large online stores, sites of large companies with many pages of news and promotions.
4. Large portals, forums, multi-online stores.
5. Constantly developing sites of large startups, social. networks, corporate portals, search engines.
Well, or offer your scheme / hierarchy and write what you use for what and most importantly why?

Answer 1

The answer to why is simple: all these things make our life better :)
for 3-5 I advise you to use:
- a preprocessor (everyone has their own taste, for example stylus)
- a build tool (there is also something for everyone, for example grunt)
- a version control system (git)
- nb (for example, bem, mcss)
- templating engine (each has its own, depends on the cms on the basis of which you work, or which your progers made)
- graphic editor (photoshop is our everything :) + css hat, enigma64)
- ask specific questions on the toaster ru ;)
I advise you to use 1-2 technologies from the list in each new layout from 1-2, then you will get involved and will not let go))
ps Well, this is an approximate list, more to come ;)

Answer 2

my choice - angular and less
will suit all categories)