I guess it's understandable to have some confusion since bioinformatics can span a wide range of topics. If you are asking because you are thinking to apply for a junior position (say PhD, postdoc, research assistant) then just look up job descriptions that would appeal to you, some are more oriented on software/database design, other on developing methods, other on data analysis. You ask for a detailed answer but you give us very little detail about your profile and your interest!
Since you ask about a junior position, I think what matters a lot is your attitude rather then your hard core skills. I mean, for many bioinformatics jobs it's important to think quantitatively, be organised, and ready to learn new skills, be curious. For example, if you don't R but you know, say, statistics and matlab you are perfectly fine, provided that you are willing to learn R (but you might be able to avoid it altogether, I'm just making a point). Or again, I think it's fine to apply for jobs on NGS data analysis skills even if you don't have experience on NGS but you are comfortable handling large datasets.
To get a feel of what you need know and do, it might be useful to pick some papers that you wish you contributed to and try to reproduce them (hopefully they don't require prohibitive computer power...). I guess it's fine to post on Biostars and/or to the authors any problems you encounter on the way. But really, to get more useful answers you should try to be more explicit about your intention (it's fine to say "I don't know myself!")...
I'll add two points to this:
In general, for junior positions, you're not expected to have a lot of experience so be sure to pick an environment in which you can learn. This means you should probably avoid positions where you'll be the only bioinformatician in a wet lab-only group until you've got enough experience.
Even in junior positions, you'll often have to engage with data producers (e.g. clinicians, biologists ...) and work in a team. So your ability to communicate effectively in a multidisciplinary environment will be even more important than your technical skills.
Second this. If by junior position we are talking graduate school, then you really aren't expected to know much of anything other than the regular undergraduate background. It varies from lab to lab and place to place of course, depending on what sort of students from what sort of undergrad programs that lab/school usually takes. Undergrad programs in bioinformatics are still fairly rare, and students come from biology undergrad programs as well as comp sci, math, or stats.