i don't understand what you are talking about by saying "What are the requirements of Search Engine Optimization?". But for good result, you should use only ethical SEO tactics which includes both on-page and off-page optimization.
You need to start with getting familiar with the concept of improving your organic web ranks over the net, through using a combination of free and paid methods. Links combined with on page elements seem to be among key players over the net today.
It is possible to make a website that would be liked by both people as well as search engines. Contents which are related to the targeted terms and original ones would be adding weight to the domains and through building links, their ranks on search engines would get improved greatly.
Search engine optimization are two -
1. Onpage optimization
Meta Tag Preparation
Keyword Research & Analysis
Web Page/Design Optimization
Mod Rewrite / Search Engine Friendly URLs
Robots File Creation
Sitemap Creation &Submission
Site Quality Check
Link Building Campaigns
SE Friendly Design
SE Friendly Programming
SE Friendly Content
2. Off Page Optimization
Press Release Submission
The first mandatory thing in SEO is that you must internet expert of online business.
Then you must aware of SEO activities like Off Page SEO and On Page SEO. These are the must two conditions or requirements for SEO.
Other than these there are lots of things you have to do in SEO or apart from SEO like SMO, video Submission PPC, Referrals etc.
This is my first post, SEO are of two types like on-page and off-page.
Off-page includes article submission, forum posting, blog commenting, directory submission.
On-page includes keyword research & analysis, title and meta tag optimization.