### Hard Reset Local branch to the origin/remote.
> This basically discard all changes, commits, etc. which are not pushed to remote yet, and pull the latest version from the remote.

```bash
git fetch origin master
git reset --hard FETCH_HEAD
git clean -df
```

### Managing sub-module repos.
> This will add external repositories as submodules into the current repository.

```bash
git submodule add <repo-url> <sub-module-name>

```

> This is how you clone a repository that contains submodules.
```bash
git clone -recurse-submodules -j8 <main-repo-url>
```