What is follow and no follow in webpages and SEO?

Answer 1

Do follow means you want the search engines to follow the external link and bring the link juice (the authority PR) of this site with him. As an owner of a website, you want do follow links linking to your site from high PR sites. No follow links are basicly telling search engines no to crawl further then the one site.

Answer 2

The robots META tag is written as:

You can use all lowercase on these, or ALL CAPS.

You can omit the space between each one, or use a space between each one.

Inside the content=""

• You can add these DO instructions: index,follow,snippet,cache
  
• OR
• You can add these DON'T instructions: noindex,nofollow,nocache,nosnippet
  

However, for SEO purposes, you would most often include these 2: index,follow

OR for SEO purposes, you could include these 3: index,follow,snippet

In this blogpost, "Google Explains The NOINDEX, NOFOLLOW, NOARCHIVE & NOSNIPPET META Tags"

Barry Schwartz(February 23, 2007 at 9:26 am) gives an easy to understand description of each meta robots tag.

Basically:

index - means that bots SHOULD list this page as part of your website.

follow - means bots SHOULD follow the links on this page

snippet - means Google SHOULD add a snippet from this page under the Search Result in Google

cache - means Google CAN save your page in THEIR database to present the cached page to visitors

Most people (businesses to hobbyists) want the first 3. Some businesses reject using "cache" because they feel it does not force Google to present the most up to date page.

Reasons people might not want to use some of these (and instead use no in front of each):

1. You are rotating content between 3 pages. This month, you want Page 1's links to be follow(ed) with snippet. But you don't want Page 2 and 3's links to be follow(ed) with snippet.
2. You have good content, but you want to present something else and hold old content for reuse later.
3. A page is not ready for public view yet.
4. You made a dummy, template page.
5. A page is just for yourself or family members.

But most often, most ordinary people use: index,follow,snippet and if having page info cached doesn't matter, they also use cache.