diff --git a/content/roadmaps/103-react/content/101-react-advanced-topics/105-portals.md b/content/roadmaps/103-react/content/101-react-advanced-topics/105-portals.md
index a51e282fd..9c058799e 100644
--- a/content/roadmaps/103-react/content/101-react-advanced-topics/105-portals.md
+++ b/content/roadmaps/103-react/content/101-react-advanced-topics/105-portals.md
@@ -1 +1,6 @@
-# Portals
\ No newline at end of file
+# Portals
+
+Portals provide a first-class way to render children into a DOM node that exists outside the DOM hierarchy of the parent component.
+
+Free Content
+Portals in React
diff --git a/content/roadmaps/103-react/content/101-react-advanced-topics/106-error-boundaries.md b/content/roadmaps/103-react/content/101-react-advanced-topics/106-error-boundaries.md
index f403aecd8..b373c8ee7 100644
--- a/content/roadmaps/103-react/content/101-react-advanced-topics/106-error-boundaries.md
+++ b/content/roadmaps/103-react/content/101-react-advanced-topics/106-error-boundaries.md
@@ -1 +1,8 @@
-# Error boundaries
\ No newline at end of file
+# Error Boundaries
+
+In the past, JavaScript errors inside components used to corrupt React’s internal state and cause it to emit cryptic errors on next renders. These errors were always caused by an earlier error in the application code, but React did not provide a way to handle them gracefully in components, and could not recover from them.
+
+Error boundaries are React components that catch JavaScript errors anywhere in their child component tree, log those errors, and display a fallback UI instead of the component tree that crashed. Error boundaries catch errors during rendering, in lifecycle methods, and in constructors of the whole tree below them.
+
+Free Content
+Error Boundaries in React
diff --git a/content/roadmaps/103-react/content/101-react-advanced-topics/107-fiber-architecture.md b/content/roadmaps/103-react/content/101-react-advanced-topics/107-fiber-architecture.md
index c352cf6a8..951dfef4b 100644
--- a/content/roadmaps/103-react/content/101-react-advanced-topics/107-fiber-architecture.md
+++ b/content/roadmaps/103-react/content/101-react-advanced-topics/107-fiber-architecture.md
@@ -1 +1,9 @@
-# Fiber architecture
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+# Fiber Architecture
+
+React 16.0 was released with an update to the React core algorithm. This new core architecture is named “Fiber.” Facebook has completely rewritten the internals of React from the ground-up while keeping the public API essentially unchanged; in simple terms, it means only changing the engine of a running car.
+
+Free Content
+React Fiber Architecture
+Understanding React Fiber Architecture
+
+