title: How to authenticate user in browser using AWS Cognito?
body: <p>I need to authenticate users in browser (not mobile app) using AWS Cognito with username/pass, not FB/google IdProviders. </p>
  
  <p>There are a lot of docs but they seem to be separate blocks which either incomplete, do not fit the requirements or do not fit each others :(</p>
  
  <p>I created Cognito User Pool, then Identity pool and tied the userPool to the idPool, then I stuck. Do not know which library to use and how to use it. 
  The closest I find are: </p>
  
  <ul>
  <li><a href="https://aws.amazon.com/sdk-for-browser/" rel="noreferrer">https://aws.amazon.com/sdk-for-browser/</a> but my experience is not enough to convert their FB samples to not-using FB</li>
  <li><a href="https://github.com/aws/aws-amplify" rel="noreferrer">https://github.com/aws/aws-amplify</a> but using this lib I'll have to study React/Angular from the very beginning (I'm not a front-end developer, sorry) and I have no clue how to convert their npm-based samples to front-end javascript (npm is for NodeJS thus back-end, isn't it?).</li>
  </ul>
  
  <p>All I need is plain html form with username/pass, send the request to Cognito and a way to check during the next page load whether the password was correct. If it matters I will use AWS Lambda as back-end for processing future tasks.</p>
  
  <p>How can I do it? Is there a tutorial/doc for my case?
  Thank you.</p>