Q:

what kind of data can we extract from a blog or a forum for a web scraping project?

I am about to work on a project about 'analysing data from blog or forum' so I am wondering what kind of data can we extract from a blog or a forum and how should I get started

A:

First, you should decide which programming language to use. Then, you should consider using a web scraper.
There are different ones for different programming languages. For Java, there is jsoup for example. 
As to what data can be obtained you have to first consider the format of the page. But data that I would recommend collecting consists of:
Usernames
Photos on the site
Data related to usernames (Join date, Number of posts, Premium member status, Photo, Phone numbers, E-mail addresses, Full name, address, etc. (if applicable)), 
Title of blog posts, 
Questions asked on forums, 
Number of answers for each question, 
Typos in the blog post, 
Date related info.

