spam on blog comment...good or bad

there are many spamming comments on my wp blog post.
Is it good or bad for my blog & how to prevent it
maximum of comments are like this

 

Well, the first question must be a joke, right???

Enable the Akismet plugin on your blog.

Install a plugin like this http://wordpress.org/extend/plugins/wp-recaptcha/

You can read this too http://www.net-security.org/article.php?id=987&p=1

 

if you want to have the "spamest" blog, yes, thay are good

as @ilook said, akismet will help you a lot.

 

First of all get Akismet working...

If that still doesn't stop then have your visitors register before they can post a comment.

 

for blog owner, the spam comment is really bad for your blog, and for the spammer please dont make this like there is nothing a time to do some good comment (at least relevant), and to minimum this spammer we need to use aksimat plugin, reCAPTCHA plugin.

 

I also have this problem at 1 of my blog. It's really annoying...