Update system design note.

docs/techs/System-Design/Grokking-the-system-design-interview/Components/Kafka.md

@@ -27,7 +27,7 @@ Publish records to Kafka
 
 ### Consumers
 
-Subcriber of kafka topics.
+Subscriber of kafka topics.
 
 ### High Level Architecture
 

docs/techs/System-Design/Grokking-the-system-design-interview/Problem-set/1.TinyURL.md

@@ -1,9 +1,12 @@
 ---
-title: TinyURL
 date: 'January 29, 2022'
 tags: ['System-Design']
 ---
 
+# TinyURL
+
+[System Design : Scalable URL shortener service like TinyURL](https://medium.com/@sandeep4.verma/system-design-scalable-url-shortener-service-like-tinyurl-106f30f23a82)
+
 URL shortening is used to create shorter aliases for long URLs.
 
 ## Requirements
@@ -23,10 +26,10 @@ URL shortening is used to create shorter aliases for long URLs.
 
 ### Extended requirements
 
-* Telemetrics: how many times a reduction happened?
+* Telemetry: how many times a reduction happened?
 * REST APIs by other service.
 
-## Capacity Estimation and constriants
+## Capacity Estimation and constraints
 
 **Read-heavy service**: R:W = 100:1
 
@@ -44,7 +47,7 @@ URL shortening is used to create shorter aliases for long URLs.
 
 **Read**: 20K URL/S
 
-### Storate
+### Storage
 
 Store URL in 2 years:
 
@@ -130,13 +133,13 @@ No relationship between objects.  No-SQL for availability and horizontal scalabi
 
 How to generate a short and unique key for a given URL?
 
-### Encoidng actual URL
+### Encoding actual URL
 
 [MD5](https://en.wikipedia.org/wiki/MD5) or [SHA256](https://en.wikipedia.org/wiki/SHA-2)
 
 [Base64](https://en.wikipedia.org/wiki/Base64#Base64_table) with 6 letters long. 64^6 = 68.7 Billion
 
-MD5sum to generate hash. 128 bits.
+MD5Sum to generate hash. 128 bits.
 
 #### How to resolve hash collision?