Due to the nature of one my websites, I plan to make it multilingual and I'm unsure of how to handle it in terms of accessibility. I'm currently considering two things, having the non-English version as otherlanguage.domain.com or domain.com/otherlanguage. I'd use the initials for that language though rather than the full word, so which do you think would be better in terms of accessibility for the user?

Now I doing multilangual site -> and languages:

cz.domain.com
en.domain.com
sk.domain.com

I don't really see many reasons why either would be better than the other for accessibility. Either are pretty simple to remember if the domain itself isn't too much of a problem, you're not planning anything complicated.

I would assume the abbreviation would be sufficient as the user would know their countries abbreviation.

However, like Abbie said, I guess it would be your preference as the alternative is not a bad option either.

Thanks for the input, I guess I'll have to do some polling on my own to get a better idea though as the audience I'll be targeting is not technical by any means so I doubt it's as obvious to them. Although I will say that the subdomain method certainly looks cleaner and yes, my domain is not complicated at all so it shouldn't be a problem I hope.

or you can just get domains according to the counties whatever.co.uk, whatever.co.nz, whatever.us etc

I think XStream-Hosting is right, you should go for country specific tld, I hope you'll get SEO leverage with such domain names and it would be easier for you to target your audience for specific country through geo-location.

extra TLD's are nice, but remember that requires extra marketing and work on the part of your SEO. Pagerank will start at ZERO for each domain until you build a reputation and have people linking to your domain (this is true aslo of the subdomain method you were thinking about).

MOST places will put domain.com/fr/ or domain.com/de/ when it comes to language options as this will at least let the pagerank and recognition in google to trickle down to your folders.

Goinw with subdomain or with new domains means you must market each one and you become a small fish in a big bowl. Using an existing domain allows you to keep the rank you've already gained, and then just add more on top of it.

Using as subdomain (en.website.com) - google reads it as a bit different website, but not always. About it you can read here:
http://searchengineland.com/how-chan...pact-seo-12899

Be sure they will be diffrent domain names and you will need to do the SEO for the each of them separately

Definitely the subdomains (yahoo style)

^ If you want to do "yahoo style" you should brand your website first to that level.