Do you have to be friends with your co-workers?

Being friends with your co-workers I think isn't such a huge deal. You don't exactly have to be friends with them, like always hanging out out of work and doing things together but I do think it is important to not be complete strangers. Being strangers with your co-workers isn't a good thing because you guys will eventually have to communicate while at work. Being friends can be a good thing since I guess you guys can do things together after work or while at work you guys can have good communication. Not being friends can be difficult because maybe in your workplace you will feel like you need somebody to speak to. You guys don't have to be mega friends but being friends and being okay with their presence is important. You don't want to have to work with strangers and people you don't like at work.