Yes, pagerank is important for a website so that its keywords get better rankings.But there are a lot of websites which have less page rank and their keywords get better ranking.
Nowadays all of the social media sites provides only nofollow link and does not add up to a main backlink for the website.However, it will help to increase the traffic of the website.
Info-graphics is a statistical and graphical representation of a set of topics or a comparison of the same topics categorized over the years.It needs data collection,creating data patterns with softwares
PPC is pay per click which consists of entire ad copies,keywords,campaings,display network,banner ads.CPC is Cost per Click where the cost of a single keyword is calculated and is analyzed for many campaigns.
You have to perform online reputation management (ORM) in order to remove the negative reviews,comment for the business.Its a long process and would take time.
For removing negative reviews,comments concerning a business or a product, online reputation has to be done which is the process of increasing the branding,and reputation of the company or business in a positive way.
Cloaking is a black hat technique which is used in website to show a different content to the user and different content from the server side to the crawlers.This is done for getting better positions in the google search results.But websites will get penalized if these techniques are used.
Backlinks help in the promotion of the keywords of the website.High quality acquired backlinks helps to increase the page rank,positions but low quality backlinks can lead to penalization and also spamming which affects the website in ranking for the keywords.
Social media sites are useful only for branding and getting visitors since all of the websites are using the nofollow attribute and hence backlinks cant be obtained.