The words kres, skraj, granica - synonyms?

Czesc!

I'd like to know if the words kres, skraj, granica are synonyms.
Can they mean the same thing?

thanks

granice - border
skraj - edge, i think

kres - end, stop
skraj -edge
granica - border .... granice - borders

I agree with the above explanations and now my 2 cents (or "moje 3 grosze").
The normal (most common word) for "the end" is koniec,
There's also one more synonym that you left out: kraniec

skraj is used for example in "na skraju lasu", "na skraju/obrzeżach miasta"
granica can also mean limit, the word "limit" is also used in Polish, but usually in a financial context (for example "limit wydatków" - limit of the expenses, "mieć limit kredytowy" - to have a credit line open with a fixed maximum amount, I don't know how to say it more precisely in English, probably simply "to have a credit limit").

In maths you can use the word "granica" or "limes" (limes = limit in Latin) for example of a function (granica górna/limes superior = upper limit of a function; granica dolne/limes inferior = lower limit of a function)

some fixed expressions
być u kresu sił - to be exhausted, at the limit of one's forces
Kresy (maiuscule K) or Kresy Wschodnie - Poland's eastern lands in the Polish-Lithuanian Commonwealth and between WWI and WWII, now Ukraine, Belorus.
kresowiak (plural kresowiacy) - a person from "Kresy"

przekroczyć granicę - 1/ (literally) to cross a border, 2/ (figuratively) cross the limits, overstep, go too far

na krańcu świata - at the end of the world (end meant in the geographical sense)

koniec świata - end of the world (in the apocalyptic sense)

żyć na krawędzi - to live on the edge

well, I guess "skraj", "krawędź", "obrzeże" fall into a separate category (edge, bound, periphery, boundary)

koniec, stop? :D

thanks krzysztof. as always, good stuff. :)

I just asked because an online dictionary says, for example, that the word skraj can mean "edge" and in other contexts it can mean "border", "outskirts", as you can see in the image. So it made me wonder. Anyway, thanks for answering.

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  skraj.JPG
  

Using a dictionary isn't as simple as one might think :)
I always have a good laugh reading some texts in English written for example by a Chinese - they have the tendency to choose a random word from a dictionary and use it in a completely wrong context.

However 'brzeg' can also translate as 'edge', though perhaps more in the sense of 'river bank'/ the river's edge. I have often seen 'na brzegu rzeka' = on the bank(s) of the river.

na brzegu rzeki
You're right, also:
brzegi jeziora
nad brzegiem morza
(it's generally used with for any water basin's edge, you can't use the word "krawędź" or "skraj" here)

brzeg is just another word for "krawędź", and can also be used when saying about an edge of a rectangular surface, for example "brzeg stołu" "edge of the table).

As I said before choosing between synonyms from a dictionary can be hard, you need some experience and sometimes quite a good knowledge of the language (of course there are also simple cases, when a foreign word has one translation only, but this isn't a rule)

Much appreciated, as always! I was thinking the same regarding the latter e.g. 'naD RenEM' (on the Rhine, i.e. along the banks of the Rhine) etc.