Outbound links are links that you have on your website linking to other websites.
Inbound links are links on other websites linking to your website. People wanting to link to your site shows that they believe your site is interesting, informational, or useful in some way (which is what people are really searching for on the internet anyways).
The number of other sites linking to yours can also indicate your sites popularity. If you don’t know if you have any inbound links there are many different tools you can utilize online to find out.
The best part of inbound links is the advantage it gives in search engine optimization. Google recognizes the number of inbound links as this popularity indicator. Therefore, the more sites linking to your site, the better you will rank in the SERPs. Sometimes you will get lucky and people will naturally link to your site.
However, emailing other developers with sites relevant to your site and asking them to link to you is also a good practice. In return you can offer to link to their site, increasing their rank as well. Some search engine optimizers often practice paying for a link to be on a site.
Be cautious with this practice. One reason to be cautious is Google doesn’t like people paying for a link to their site. However, how are they really going to find out that you are paying, right? So I guess just don’t get caught!
Another reason to be cautious is because you may end up spending more than that is really worth. I would advise mainly just communicating with the other website developer and help each other out by both linking for free.
Once you have an inbound link from another site you must take further steps to optimize your links. Many sites will put ‘click here’ or other nondescript words for links to other sites.
You do NOT want this kind of description for your link. Once again, you will need to communicate with the other developer to try and get the description you do want. You will want to use those important keywords once again in order to optimize those links and have the search crawlers better recognize them.
Another thing to consider when having other sites link to you is how those sites are relevant to your site. Google has started cracking down on link spamming, or the idea of just posting links to your site wherever you can. The search crawlers are comparing the anchor text from links with the information on the website for a relevant correlation.
You might as well not take the time spamming your link everywhere and spend the time getting inbound links the correct way. In the long run, it will be much more advantageous to your website.