Hikkikomori and social anxiety

Hi guys! Today i was watching an anime named N.H.K ni yôkoso. this anime coined the name Hikkikomori. the story is about a guy who is housebound and cant go outside. From what i have learned from web some saying hikikomori and social anxiety are not exactly the same thing. can someone tell what are the key differences between social anxiety and hikikomori. also what does NEET mean??

A hikikomori doesn't necessarily have social anxiety. His reasons could have to do with other things, like feelings of inadequacy, worthlessness, and so on.
Social anxiety doesn't mean you withdraw from social life, it means you get anxious in certain situations, but not necessarily in all social situations.
A person with social anxiety might still go outside often and even have a job, or go to college, and so on. A hikikomori is more like a shut in, and the reasons for it might not be social anxiety.

Regarding Welcome to the NHK, the main character likely suffers from agoraphobia.

Thanks for your responses guys. Looks like i have got a new subject to learn.

I consider myself as hikikomori as well. I agree that not every hikikomori must have social phobia or agoraphobia but I think most must have it in some degree.

https://www.youtube.com/watch?v=CKRpx2Ahbmk
I think this is a really harsh way to help a hikikomori. Forcing her to leave the house suddenly when she might not have been leaving the house for years must be a real nightmare for her. I felt bad for her.

I have to admit the video you posted scared me. I feel sad for the girl. i believe the inner hell is the the most disturbing place on earth. once its opened it can kill a persons soul little by little. no matter how much one try to fed it its hunger wont go way. it takes real effort to close that door. i have a huge respect for these people . the amount of inner suffering they go through the dwell against ones own mind can eat up lot of energies. A strong willed mind is needed to tackle all these problem.