update backends tutorials intro (xarray-contrib#266)

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Co-authored-by: pre-commit-ci[bot] <66853113+pre-commit-ci[bot]@users.noreply.github.com>

Author: JessicaS11

advanced/backends/backends.md

@@ -1,44 +1,49 @@
-# Creating new backends
+# Reading data using backends
 
 ## Introduction
 
-You can [read different type of files](https://docs.xarray.dev/en/stable/user-guide/io.html)) in `xr.open_dataset` by specifying the engine to be used:
+You can [read different types of files](https://docs.xarray.dev/en/stable/user-guide/io.html) in `xr.open_dataset` by specifying the engine to be used:
 
 ```python
 import xarray as xr
 xr.open_dataset("my_file.grib" , engine="cfgrib")
 ```
 
-For each available engine there is an underlying backend, that reads the data and pack them in a dataset.
+Navigating Xarray backends can be confusing,
+so we recommend checking out [this flow chart](https://docs.xarray.dev/en/stable/user-guide/io.html)
+to help you figure out which engine you need and how to use it.
 
-Xarray bundles several backends internally for the following formats:
+You can see what backends are currently available in your working environment
+with `xarray.backends.list_engines()`.
 
-- netcdf4 - netCDF4
-- scipy - netCDF3
-- zarr - Zarr
-- pydap - DAP
-- ...
+## Why use the Xarray backend API to write your own backend?
 
-External Backends that use the new backend API (xarray >= v0.18.0) that allows to add support for backend without any change to Xarray
+- Your users don't need to learn a new interface; they can use `xr.open_dataset` with the `engine` kwarg.
+- With little extra effort you can have lazy loading with Dask. Simply implement a function for reading blocks and Xarray will manage lazy loading with Dask for you.
+- It's easy to implement: using the backend API (introduced in v0.18.0), you don't need to integrate any code in Xarray.
 
-- [cfgrib](https://github.com/ecmwf/cfgrib) - GRIB
-- [tiledb](https://github.com/TileDB-Inc/TileDB-CF-Py) - TileDB
-- [rioxarray](https://corteva.github.io/rioxarray/stable/) - GeoTIFF, JPEG-2000, ESRI-hdr, etc (via GDAL)
-- [xarray-sentinel](https://github.com/bopen/xarray-sentinel) - Sentinel-1 SAFE
-- ...
+## More Information
 
-## Why using the Xarray backend API
+See the [documentation](https://docs.xarray.dev/en/stable/internals/how-to-add-new-backend.html) for more details on adding and registering a new backend.
 
-- Your users don't need to learn a new interface that is they can use `xr.open_dataset` with `engine` kwarg.
-- With little extra effort you can have lazy loading with Dask. you have to implement a function for reading blocks and Xarray will manage lazy loading with Dask for you
-- It's easy to implement: you don't need to integrate any code in Xarray
+Follow the tutorials on creating a new backend for binary files.
+
+```{tableofcontents}
 
-## Next
+```
 
-See the [documentation](https://docs.xarray.dev/en/stable/internals/how-to-add-new-backend.html) for more.
+### Links to internal backends
 
-Follow the tutorial on creating a new backend for binary files.
+- [netcdf4](https://pypi.org/project/netCDF4/) - netCDF4
+- [scipy](https://scipy.org/) - netCDF3
+- [zarr](https://pypi.org/project/zarr/) - Zarr
+- [pydap](https://pydap.github.io/pydap/) - Data Access Protocol (DAP/DODS/OPeNDAP)
+- [h5netcdf](https://h5netcdf.org/) - hdf5
 
-```{tableofcontents}
+### Links to external backends (not comprehensive)
 
-```
+- [cfgrib](https://github.com/ecmwf/cfgrib) - GRIB
+- [tiledb](https://github.com/TileDB-Inc/TileDB-CF-Py) - TileDB
+- [rioxarray](https://corteva.github.io/rioxarray/stable/) - GeoTIFF, JPEG-2000, ESRI-hdr, etc (via GDAL)
+- [xarray-sentinel](https://github.com/bopen/xarray-sentinel) - Sentinel-1 SAFE
+- ...