As i understood from your question, you want to know is there any difference between crawlers of Google? And the answer is no. Google has many data centers and each of them have different IP but the WEB crawler of each of them are the same. Google also has image crawler for indexing images ,Mobile crawler and Adsense crawler. But for most usual websites the most important is Google web crawler for indexing the text of websites. I hope i understood your question well.
If you want to know useragent type then below are some of bots type. User-agent: Googlebot-Image User-agent: Googlebot User-agent: Mediapartners-Google
Also mobile. Just visit webmaster tools and on page whre you can validate your robots.txt you can see different google robots.