Ok I was trying not to get too detailed with my original answer.
Pointing and forwarding are the same, in which you are directing one domain to "hop" to another.
Pointing is when the two domains are on the same hosting account- forwarding is when they are not.
So for better examples:
Pointing: Both mysite.net and mysite.com are owned by you and hosted on HostGator. mysite.net points to mysite.com visitors can type either URL and it takes them to the same place.
Pointing is the term also used for when you prefer to switch hosts but want to keep your domain under the same registrar. You would notify your registrar to change your current DNS settings to those of the new host account.(you can, most times, do this step yourself if you want)
Forwarding: You have another website hosted elsewhere for an ebook for sale at ebooksale.com. You want people to click from mysite.com to get to ebooksale.com but when they hover over the link on your site you want them to see mysite.com/ebook so it looks like they are not leaving your site. You would forward mysite.com/ebook to ebooksale.com. They click and it sends them to your ebook site.
As for
SEO purposes, you'll have to check with Tess on that, she's the expert.