WordPress is the dominant Content Management system for websites over the internet. WordPress is an open source platform that allows website owners to create websites in minutes, and start publishing immediately.
To certain extend, starting a website using WordPress does not need deep technical skills, there are countless number of guides over the internet; that provide a step by step guidance to create websites for people who have little technical knowledge.
WordPress itself is a platform designed to work by plugins that provide functionality; WordPress alone is just a simple publishing platform that depend on plugins.

Wordfence Security
Free plugin provides application layer firewall and malware scanner to protect WordPress installation.
It comes with installation wizard to ease site owner work of choosing features to protect the website, going deep to understand every bit need further technical skills, while going on the development team recommendations provide high level of security protection to the website. There is a premium version that provides extra support and delegate lots of the hard work and technical required expertise to the professional team in Wordfence.

W3 Total Cache
WordPress as platform is not providing caching functionality out of the box, as website grows and content increase it getting slow by time. Therefore caching is essential for any WordPress installation, W3 Total Cache is one of the best free caching plugins.
It will improve the SEO and user experience of WordPress site by increasing website performance, reducing download times via features like content delivery network (CDN) integration.
This will help boost WordPress website speed quite considerably by compressing the code and much more, and of course improve user experience.

Akismet
Spam is killing internet forums and websites, WordPress sites are great target for spammers because they provide built in support for commenting on blog posts. No one likes to sit back and look at each and every comment received and then decide if it is a spam comment or not. Akisment plugin eases out efforts when it comes to segregating the spam comments from the good ones.
Contact Form 7
Attractive plugin that automatically let WordPress site owner to handle several contact forms. It allows the site webmaster to customize forms, and email responses with ease clear written guidelines. The functionality provided by “Contact Form 7” supersedes many other plugins in providing customizable easy to use forms, with a dashboard that registers all submissions per form.

Google XML Sitemaps
Google is the dominant place for search, if a website want to get the most from Google Search engine, the website must feed Google Search engine with the links, and content. Google XML Sitemaps is one of the WP plugins that do the job. It is important because it improves SEO by helping engines, such as Google and Bing, find WordPress website and see its complete structure.

Redirection
Website looks unprofessional when online visitors hit the wall of 404 page errors, it can leave a bad taste in the mouths. Publishing and replacing content in a website can generate dead links in website.
If content changed the URL of a page as it is shown in search engine results, then a 301 redirect is needed. Redirection plugin do that, without needing much tech knowledge, and alert website owner if there are any 404 pages that need to be attended.

Page Builder
SiteOrigin is a free plugin that makes it easy to build responsive grid-based page content that adapts to mobile devices with pixel perfect accuracy. It will help creating nice home pages, contact, about us or any other page where a linear layout will not convey website message.
A simple drag and drop interface means allows Page Builder to do what it does best – all the difficult work, generating lightweight, SEO-friendly code.