What are DoFollow vs NoFollow Links?
 

By default all links are dofollow links. And when some one put nofollow attribute into the link. then it's become nofollow links.

Dofollow Links are those links from which we get link juice and it's very helpful in SEO strategy. You can get your website more high into alexa ranking.

Nofollow Links are those links from which we do not get any link juice but still it's alive to get traffic just. not link juice.

Nofollow is an attribute from which we tell to search engines that do not follow this link ranks.

Good article about the difference between DoFollow vs NoFollow links.It was really helpful in understanding the difference.

In order to improve your keyword rankings in Google it is important that other sites place links (backlinks) that point to your site. The higher the PageRank of a remote site the greater the impact on your rankings. Apart from the PageRank it is for link builders also very important to know whether placed links are nofollow or DoFollow. What does this mean though?
A backlink posted from a website with a high PageRank receives a bit of that PageRank and sends it to your site, it is also referred to as 'Link Juice'. Just bluntly taken it means Pagerank via a backlink from a site to another 'flows'. As a site administrator, you can block this Link Juice Flow through a link on the property nofollow add. For example, look at the English wikipedia site about the topic nofollow and scroll down to the section called References. This Wikipedia page has a PageRank of 7. The links in the references to external pages, however, receive nothing from this PageRank. For example, look at the source of the page. In FireFox and Chrome - right click and select 'View Page Source' (Show Source) and Internet Explorer is the 'View Source' (Show Source). Search with CTRL-F on 'the nofollow attribute and SEO. Then you will see a comprehensive piece of text with various terms. In it is hidden the following code snippet:
Wikipedia appends this piece of code to links pointing to sites outside the domain wikipedia. Facebook and other major social media sites do the same. So you can unfortunately not score some easy high PR backlinks like this. When the piece of code as above is missing, then the link is automatically DoFollow and passes some PageRank through. It is therefore important when link building to check if the website you want to put links even allows DoFollow links.
Do you need to check for it in the source code each time? Luckily, you don't. There are several plugins available for your browser that allow you to see at a glance whether DoFollow backlinks are allowed. The browser addon Search Status for Firefox shows all nofollow links on a website highlighted in pink. SeoQuake is also suitable for this and also has many other useful SEO tools. Both Internet Explorer and Chrome lag behind in terms of good SEO browser plugins. I therefore am not going to recommended anything for these browsers. I simply recommend whilst link building to use as a standard the FireFox browser.
Finally, a word about link variation. It is important to get DoFollow backlinks from websites with a high PageRank in order to promote your google rankings. Google does not like unnatural link patterns. Make sure also that when you link build you also build some nofollow links to your site.

HI I think Do Follow link is the best compared to no follow.

The links in which rel=nofollow appear are called nofollow links and it is a direction to search engine not to crawl the hyperlink. Webmaster also consider it as not providing any link juice. We must have both types of links because they require for supporting your information. In my opinion we should have both types of the links.

do follow create link juice whiel no follow does not create link juice for crawler

They are link attributes which contain instructions for search engine robots. No follow links are never crawled and hence not indexed in search engines, whereas do follow links are indexed and are helpful to build keyword ranking. No follow links are only helpful to generate traffic to your website from various external webpages.

Finally, what is better for my website?

Hi,
DoFollow links provide link juice but NoFollow links not provide link juice for crawling

Dofollow Link: if a link doesn't have a rel attribute then it's a dofollow link.
nofollow Link: Nofollow link is a value that can be assigned to the rel attribute of an HTML a element to instruct some search engines that the hyperlink should not influence the ranking of the link's target in the search engine's index.

Do follow links are very helpful from SEOs perspective. Every SEO professional use DO Follow links only to rank a website in different search engines as it helps to click on the link to directly land on the website home page.

No Follow doesn't help a much on the website ranking. It has been used to provide to the info related to any important topic.