Does domain name affect seo ,, what if I have only 1 keyword in domain name ,, or no keyword in domain name ,,, a want to start a tech blog , is having "bit' in domain name good/OK? Its not gonna be a electronics related blog just purely tech stuff (except ec) ,,
Q seo effects of having a top level domain vs a national level domain (.com/.net vs .in)
Q .com vs .net. Seo affects
There are lots of questions...
Does domain name affect SEO. Simple answer, Yes. It does.
What if I have only 1 keyword in domain name That's Good. Having at least one keyword in domain name is better than 0.
SEO effects of having a top level domain vs a national level domain Country level domains are good if you want to target a specific country. If you want to target global audience then don't buy country specific domain. And you can confirm this on searches. When you search on country specific Google website, you will see country specific websites are given weightage over global websites.
com vs .net. SEO affects Very negligible, IMO. Although Google has mentioned that domain TLD does not matter but that's not true in practice. TLD matters when you use .com vs .co/.in but not really in case of .com and .net
Does domain name affect [SEO]
Yes, to a small degree, but not nearly as much as content nowadays.
To rank highly, the content of your page must match certain criteria as implemented by the search engine listing your page. Here is a link to Google's Webmaster Guidelines to give you a rough idea of the more technical aspects of what they would like your page(s) to look like.
[W]hat if I have only 1 keyword in [the] domain name [] or no keyword in domain name[?] [I] a want to start a tech blog, is having "bit" in domain name good/OK?
Yes, that is perfectly acceptable.
As mentioned, the content is what matters most. You may want to research specific key words on Google Trends for popularity, either for inclusion in your site name/tags or, more usefully, for target topics you may wish to write about.
[What are the SEO] effects of having [a particular gTLD/ccTLD?]
If you are producing content for a particular country/language, try to use an appropriate ccTLD (country domain). For instance, if your audience is primarily Swedish and you will be writing articles in Swedish, try to choose a .se (Swedish) domain. This will help your ranking with that audience.
If you are writing something that will be read by a larger audience than one country, or simply wish to have a "wider" gTLD (generic domain), you can use .com, .net, .org, etc. Note that there are a lot more gTLDs now (ex. .ninja .eat, .xyz ...). However, at least with Google, the exact gTLD shouldn't matter much. That is, they should ideally have no impact, positive or negative, on the SEO ranking of your website.
You can find a few more details on Google's policy in this July 2015 blog post.
Other Considerations
As a suggestion, try to pick something that resonates with your readers. Though taken apparently, something like "techbit.com" might convey quick articles on tech topics and produce the proper connotations with "tech" and "bit" (the latter having an obvious double implication).
You may also consider what the user expects to see for a gTLD. A commercial, coporate website might not want to use a .org, for example. Wikipedia has a list of the currently available ccTLD/gTLDs. Anything listed in the ICANN section in blue should be available (depending on your registrar, of course, whom will have the final list of gTLDs you can choose from).
You may also want to think about advertising. For instance, here is a quick summary of the performance of newer vs. more traditional gTLDs with Google AdWords. In particular, this article basically says that running a Google AdWords campaign on a newer gTLD (e.g. .ninja) is likely to produce similar conversions as running an AdWords campaign on a .com domain, but perhaps be somewhat cheaper.
