start: Add a parameters hidden section to experiments to merge params/metrics into experiments

content/docs/start/experiments.md

@@ -120,6 +120,33 @@ Experiment results have been applied to your workspace.
 
 <details>
 
+### ℹ️ More information about (Hyper)parameters
+
+It's pretty common for data science projects to include configuration files that
+define adjustable parameters to train a model, adjust model architecture, do
+pre-processing, etc. DVC provides a mechanism for stages to depend on the
+specific variables from a file.
+
+By default, DVC assumes a parameters file named `params.yaml` is available in
+your project. DVC parses this file and creates dependencies to the variables
+(`model.conv_units` and `train.epochs`) found in the file.
+
+Here is the contents of `params.yaml` file:
+
+```yaml
+train:
+  epochs: 10
+model:
+  conv_units: 16
+```
+
+When you use `--set-param` option for `dvc exp run`, DVC updates these values
+with the values you set in the command line before running the experiment.
+
+</details>
+
+<details>
+
 ### ⚙️ Run multiple experiments in parallel
 
 Instead of running the experiments one-by-one, we can define them to run in a