What is a Beta Reader & Where Do I Find One?

I received the following question via e-mail:

I wonder, have you blogged about how one goes about finding Beta Readers? I looked around your website but couldn't find anything, but I seem to recall from a past post of yours that you do have and value BRs. I'm a bit abashed to say I don't really know what a Beta Reader is.

A beta reader is, essentially, someone who reads your work and offers input while it is in draft form.  Generally, they look for typos, grammatical errors, continuity issues, etc. in order to help improve and polish your work before its submitted to a publishing professional or made public.  A lot of beta readers will do more than check for typographical errors, however, and will extend their generosity and time by critiquing and commenting on plot issues, characterization, believability, overall feeling, etc.  Whatever they find that they feel could use improving.  Mostly, it depends on what you want and what you and your beta reader(s) agree to.  If you're particular and/or thin-skinned, the more up front you are regarding the kind of beta reader and feedback you're looking for, the better the experience you'll have. 

Oftentimes, beta readers will turn into critique partners if you're well-matched and find yourself returning to them as a reader/critiquer.   This can be an excellent arrangement if your partner continues to be as blunt and unbiased toward your work as they were originally.

As for finding beta readers, my advice is to sign up for a writing forum like Absolute Write and to post in the appropriate section that you're looking for beta readers.  Often times, writers looking for beta readers will offer to do the same in return.  If you're not already a member, you're likely to get a better response if you post around the forum for a while first.  Get involved, make a name for yourself, give back. 

Another way to find beta readers is to use your blog, if you have one.  Just put a post up detailing what you're looking for.  Some of your regular readers might be more than happy to help. 

Basically, If you have a way to connect with other writers, use it.  If you don't, start putting yourself out there and network.

In my opinion, it's good to use both non-writers and writers for beta readers as they'll approach the task differently, so don't be afraid to use your family and friends as well.  Just don't solely rely on them.  Unbiased advice from someone who knows the ins and outs of writing has its benefits.

Now, let's turn the question over to everyone else.  Where do you find your beta readers? What do they generally do for you?