Add content for Scaling (#1030)

* Add content for Scaling

- Add description and resources for vertical and horizontal scaling
- Fix typo

* Update 103-horizontal-vertial-scaling.md

Co-authored-by: Kamran Ahmed <kamranahmed.se@gmail.com>

content/roadmaps/101-backend/content/123-scalability/103-horizontal-vertial-scaling.md

@@ -1 +1,10 @@
-# Horizontal vertial scaling
+# Horizontal/Vertical Scaling
+
+Horizontal scaling is a change in the **number** of a resource. For example, increasing the number of virtual machines processing messages in a queue. Vertical scaling is a change in the **size/power** of a resource. For example, increasing the memory or disk space available to a machine. Scaling can be applied to databases, cloud resources, and other areas of computing.
+
+<ResourceGroupTitle>Free Content</ResourceGroupTitle>
+
+<BadgeLink badgeText='Watch' href='https://youtu.be/xpDnVSmNFX0'>System Design Basics: Horizontal vs. Vertical Scaling</BadgeLink>
+<BadgeLink badgeText='Watch' href='https://www.youtube.com/watch?v=Y-Gl4HEyeUQ'>System Design 101</BadgeLink>
+<BadgeLink colorScheme='yellow' badgeText='Read' href='https://touchstonesecurity.com/horizontal-vs-vertical-scaling-what-you-need-to-know/'>Horizontal vs Vertical Scaling</BadgeLink>
+<BadgeLink colorScheme='yellow' badgeText='Read' href='https://www.geeksforgeeks.org/horizontal-and-vertical-scaling-in-databases/'>Scaling In Databases</BadgeLink>