A Question about character encoding

[adit]

I have a text file with 2 paragraphs. Is it possible to encode the first paragraph in ISO 8859-7 and the second paragraph in Windows-1254 and save the file?
Does any character encoding apply to the entire file?

[DanielWaterworth]

sure it's possible, a file is just a blob of binary. I'm not sure that text editors would recognise it though. Why not just encode the whole thing in utf8?