Back links are those links which helps to get ranking in search engines. Actually, these links create reputation over internet for your website. Good reputation helps to get ranked over search engines. That’s why it is necessary in search engine optimization. Getting Backlinks is Off Page optimization activity. Getting backlinks from trusted and relevant sites are most important to get advantage of those links. When you are given links, it will be treated outbound links for you and when you give links to other, it will be called inbound links for you.
Process of getting back links
You can get backlinks by submitting articles in articles sites. But in those articles (content of article) which are being submitted, there should be a link to your web page. That link should be anchored on relevant keyword. You can post blogs with link to your website, discuss in forums with link in signatures. You can even request webmasters of other relevant websites for creating links on their websites for mutual benefits.
Process of requesting for back links
You need to send emails to webmasters of websites, where you are willing to place link of your website. You may have to place his link first on any relevant website. Email is a good approach to request for back links.