WordPress is one of the open source CMS is currently being used by 0.6% of the total websites all over the WWW. Also after the quick wordpress installation you need to make sure you need to have some Anti-Spam plugins activated in your backend so you dont get attacked with the Auto spams which can add some bad comments and waste of time to manage your blog.
CaptchaThis! : This wordpress plugin adds a question either to spell a wordpress or a phrase, which a bot can obviously not answer. There are total of 2 options with first one being a text mode where the user needs to answer/spell out the question and in the second option the user is shown 3 options in the form of images which the user need to click on the correct image to make their comment submitted.The set up of this plugin is very easy and you can easily organise all the images for the questions , but make sure all the answer images are of equal size.
Link to CatchThis Plugin
WordPress Spam Challenge : The plugin once installed offers Customizable options and User-definable questions and answers to the commentors which they need to enter to submit the comment and instead of direct submission. The questions are framed with three numbers equated in two different equations like A + B x C or A x B +C and multiple answers can be specified.
Link to WordPress Plugin: Challenge
WordPress matriphe! KeyCode : This plugin is developed for website users who use browsers which dont allow showing images like Lynx[text-based browser] and it provides simple text as keynote.The settings are easily customizable from the admin panel and this can help out the users whose browsers don’t have image-processing library installed on their server to generate those image words and also for people who has image loading option disabled on their browsers.
Link to matriphe! KeyCode
Spam Karma 2.3 : Currently the best of all the wordpress Anti-spam plugin’s which stops the spam of all types and offers a very easy installation option.
Link to Spam Karma plugin
Akismet : The inbuilt feature of wordpress which offers excellent service by automatically sorting out all the incoming comments and adding them to the spam section so they are automatically detected and removed. If you move a comment to Spam all the future comments from the same user will be automatically moved to the Spam section offering you the best admin experiance saving time to sort out spams.
Link to Akismet Plugin