Today I Learned

We constantly learn new things. This is a repo to share those learnings.

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Table of Contents

Algorithm

• Algorithm Basics

  • Algorithm101
  • Brute-Force
  • Greedy Algorithm
  • Divide and Conquer
  • Backtracking
  • Graph
  • Minimum Spanning Tree
  • Dijkstra Algorithm

• Sorting Methods

  • Insertion Sort
  • Selection Sort
  • Merge Sort
  • Quick Sort

• Data Structure & Algorithms in Python

  • List Based Collections
  • Searching and Sorting

• Stanford Algorithm

  • Day1

Java

• Java Environment Setup

  • Multiple Java Versions in MacOS

• Java 101

  • Java Basics
  • OOP
  • Data Types
  • Variables
  • Loops & Conditional Statements
  • Array
  • Access Modifiers
  • Inheritance
  • JVM
  • GC
  • Java Memory Area
  • Collection
  • TreeSet, TreeMap vs HashSet, HashMap
  • Annotation
  • Generic
  • Static Keyword
  • Final Keyword
  • Overriding vs Overloading
  • Wrapper Class
  • Checked & Unchecked Exception
  • ==, equals(), hashCode
  • Interface vs Abstract Class, Abstract method
  • Initialization Order of Member Variables
  • Lambda Expression
  • Stream API
  • Optional Class

• Java Advanced

  • Lombok
  • Java Thread
  • JMX and Jolokia
  • Constructor vs Factory method
  • GC Algorithm
  • Guidelines for Selecting a GC
  • CompletableFuture

Spring

• Spring 101

  • IoC
  • DI
  • AOP
  • Spring Bean
  • Spring Container
  • Spring and SpringBoot

• Spring Advanced

  • Spring Security
  • Register a Spring Bean in the Spring IoC Container
  • Interceptor vs AOP vs Filter

• Spring Annotations

  • Lombok
  • @Controller and @RestController
  • @Transactional
  • @Autowired
  • @RequestParam
  • @ConditionalOnProperty
  • @ConditionalOnBean
  • @ConditionalOnClass
  • @Qualifier
  • @Valid vs @Validated
  • @EnableIntegration
  • @IntegrationComponentScan
  • @AfterReturning
  • @ConfigurationProperties
  • @AuthenticationPrincipal

• JPA Annotations

  • @Entity
  • @Column
  • @Immutable
  • @SecondaryTable

OS

• OS 101

  • What is an OS
  • System Structure & Program Execution
  • Process
  • CPU Scheduling

• OS Basics

  • What is an Operating System
  • What is Hyper-Threading
  • Process vs Thread
  • Multithread and Multiprocess
  • Scheduler
  • Synchronous vs Asynchronous
  • Blocking vs Non-blocking
  • Process Synchronization
  • Deadlock
  • Locality of Reference

Linux

• Linux 101

  • Linux Commands Summary
  • Linux Kernel
  • Linux Directory Structure
  • Use SCP Command to Securely Transfer Files
  • Linux Performance Analysis in 60 seconds
  • Ways to Check Linux OS Version in Command Line
  • tmux cheatsheet
  • Logrotate

• Arch Linux

  • What is Arch Linux
  • SLUG Meetup - Arch Linux

• Ubuntu

  • Using apt-get Commands in Ubuntu
  • Free Up Space on Ubuntu
  • Customize Your Ubuntu Terminal
  • Create Desktop Shortcut on Ubuntu
  • Settings for XDG user dirs
  • Fix AirPods not Working on Ubuntu
  • Setting a JAVA HOME Path in Ubuntu

• RedHat

  • RPM Options for RedHat Fedora Centos Installs

Server

• Server 101

  • HTTPS and SSL
  • What is NGINX
  • Scale Up and Scale Out
  • What is Cache?

• ServerLess Computing

  • What is ServerLess Computing
  • AWS Serverless Meetup - AppSync
  • Getting Started with AWS Lambda
  • Serverless Framework Setup for AWS Lambda

• Deployment

  • Deploying a Django project on PythonAnywhere
  • Deploying a Django project on Microsoft Azure
  • Deploying a Django project on Heroku
  • Using AWS S3 to Store Static Assets on Heroku
  • Deploying a Vue project on Netlify
  • Deploying a Django-Vue application on AWS EC2 using NGINX
  • Deploying a SpringBoot-React project on AWS EC2

• IBM Developer Meetup - Docker & Kubernetes

• IBM Developer Meetup - OpenShift

Network

• Network 101

  • Network Glossary
  • Protocol
  • OSI 7 Layers
  • TCP/IP
  • Encapsulation and Decapsulation
  • Types of Computer Network
  • Network Lines
  • Network Components
  • Network Address Types
  • MAC Address
  • IP Address
  • TCP / UDP
  • ARP
  • Subnet and Gateway
  • Switch
  • VLAN
  • STP
  • Router
  • Session and Cookies

• Http

  • Http Stateless
  • Http Methods
  • Cookie, Session, and Token
  • HTTP/2
  • RESTful API
  • Keep-Alive Header
  • HTTP vs HTTPS

DB

• DB 101

  • DB Basics
  • SQL and Django ORM
  • One to Many Relationship
  • Many to Many Relationship
  • Dump and Load Data
  • MySQL with Django
  • Create MySQL Users Accounts and Grant Privileges
  • How to Avoid N+1 Queries
  • Configure PostgreSQL on your Mac
  • INNER JOIN & OUTER JOIN
  • Primary key vs Unique key
  • Stored Procedure

• DB Advanced

  • SQL Order of Operations

Git

• Git Basics
• Git Tips and Tricks
• Git Branch
• Create a gitignore
• Caching your GitHub credentials in Git

Infra

• DevOps 101

  • IT Infrastructure Basics
  • What is DevOps
  • DevOps Engineer Roles and Responsibilities

• CI/CD

  • Configuring GitLab CI-CD with AWS EC2

• Jenkins

  • Jenkins Build and ECR Push

• ELK

  • Search System Basics
  • Filebeat Basics
  • Logstash Basics
  • How Logstash Works
  • Index and Shards

• Terraform

  • Terraform 101

• Ansible

  • Ansible 101

• Redis

  • Install and config Redis on macOS
  • Redis 101
  • Redis Commands

AWS

• AWS 101

  • What is Cloud Computing
  • Getting Started with AWS
  • AWS Main Services
  • AWS Main Products
  • AWS Servers
  • AWS Storages
  • AWS Database Server
  • AWS HA Load Balancing
  • AWS Analytics
  • AWS Blockchain
  • AWS IoT
  • AWS Machine Learning

• AWS Services

  • Amazon EC2 - Creating an AWS EC2 Instance
  • Amazon S3 - Creating a Bucket
  • Amazon RDS for MySQL
  • AWS CLI
  • Amazon ECR (Elastic Container Registry)
  • Amazon ElastiCache
  • Amazon Route 53
  • Amazon Athena
  • Amazon VPC

• AWS Tips

  • AWS Online Cloud Clinic #01
  • AWS Online Cloud Clinic #03
  • AWS Data Science Meetup - Amazon Personalize (03/05/2020)
  • AWS Security Meetup (07/23/2020)
  • DevAx Connect - Managing EKS Cluster Fullstack with CDK (09/01/2020)
  • AWS CDK Workshop
  • AWS Builders - Cloud Economics
  • Amazon VPC Basics
  • Amazon Security Group
  • AWS Well-architected Framework - Security Pillar
  • Find EC2 Instance by Domain Name
  • Resizing an Amazon EBS Volume
  • What Are AWS Elastic Network Interfaces
  • Estimate AWS Resource Costs
  • Understanding how IAM works

• AWS Certifications

  • Solutions Architect
  • SAA Prep Workshop
  • AWS 10,000 Foot Overview

• AWS Builders Series

  • Building My First Web Application on AWS Cloud
  • DevOps Culture Best Practices and Implementation Tools

• Practical AWS

  • VPC
  • Subnet
  • Route 53
  • Route Table
  • Elastic IP
  • Security Group
  • Network ACLs
  • VPC Peering
  • VPC Endpoints
  • AMI
  • Load Balancer

Docker

• Docker Commands
• Getting Started with Docker
• Docker Tags
• Docker Run
• ENTRYPOINT vs CMD

Kubernetes

• Kubectl Commands
• Kubernetes Basics
• EKS for Kubernetes
• What is Ingress
• How Kubernetes works
• Helm Package Manager
• Pod
• Cluster
• Namespace
• Node

Go

• Go 101

  • Go Basics
  • Variables and Constants
  • Functions
  • For Loop
  • If Else
  • Switch
  • Pointers
  • Arrays and Slices
  • Maps
  • Structs
  • Go Routine
  • init() function

Python

• Python 101

  • Python Coding Convention
  • Python Tips & Tricks
  • Python Virtual Environment
  • @property in Python
  • Generators in Python
  • Inheritance in Python
  • Type Hints in Python
  • Unit Testing in Python
  • Working with Datetime Objects and Timezones in Python
  • itertools.cycle

• Python Advanced

  • Handling Encoding Issues Using Redis with Python
  • Python GIL

Django

• Django 101

  • Django Basics
  • Variable Routing & DTL
  • Templates
  • Model
  • URL name
  • Form & ModelForm
  • Authentication
  • Request and Response Objects
  • ImageField
  • Optimization
  • Django RESTful Framework
  • Class Based View
  • DRF with JWT

Flask

• Flask Routes

GraphQL

• GraphQL 101

  • Intro to GraphQL

• GraphQL Korea Meet-up

  • GraphQL Korea Meetup (06/13/2020)

Web

• HTML

  • HTML Basics
  • HTML Sections & Outlines
  • How Browsers Work

• CSS

  • CSS Basics
  • CSS Layout
  • CSS Advanced
  • Grid System
  • Bootstrap
  • Responsive Web

• JavaScript

  • JavaScript Basics
  • Array & Function
  • JavaScript DOM
  • JavaScript Events
  • JavaScript Functions
  • JavaScript Object
  • JavaScript Basic Syntax
  • Array Helper Methods in ES6
  • Hoisting in JavaScript
  • this keyword
  • AJAX

Vue.js

• Intro to Vue.js
• Vue Intermediate
• Vue CLI
• Vue Router
• Props and Emit
• Vue Loader
• Vuex
• Vue Token

React.js

• React Hooks
• Caret vs Tilde in package.json
• Yarn vs npm
• Redux

Node.js

• Node.js 101

  • Installing Node.js using NVM
  • Intro to Node.js
  • Environment Setup
  • First Application with Node.js
  • REPL Terminal
  • NPM
  • Callbacks Concept
  • Event Loop and EventEmitter
  • Buffers
  • Web Module

• Express.js

  • Express Basics
  • EJS
  • RESTful API

Programming 101

• Programming Glossary
• How to Learn a New Language
• What is Deployment
• Vim Commands Summary
• Discrete Mathematics
• Computational Thinking
• Technical Interview Prep
• Getting Started with Open Source
• Microservices Architecture Style
• Sync vs Async and Blocking vs Non-Blocking
• Chrome Force Dark Mode Setup

Troubleshooting

• xcrun error occurred after macOS update
• Resetting the permission in /usr/local
• Brew error - compinit:503: no such file or directory
• Scouter client JVM error after macOS BigSur update