Add details from shared document into DG

docs/DeveloperGuide.md

@@ -4,26 +4,88 @@
 
 {list here sources of all reused/adapted ideas, code, documentation, and third-party libraries -- include links to the original source as well}
 
-## Design & implementation
+## 1. Introduction
+Welcome to the Developer Guide for BudgetBuddy! This guide has been created to help you current and future 
+developers of Budget understand how BudgetBuddy works and aid developors in easily adding new features, 
+fix bugs. In this guide, it will go over the main parts of the app, how they work together, 
+and why we made them that way.
 
-{Describe the design and implementation of the product. Use UML diagrams and short code snippets where applicable.}
+## 2. Setup Guide
+This section describes how to set up the coding environment, along with the tools needed to work on BudgetBuddy
 
+### 2.1. Prerequisites
+1. JDK 11
+2. IntelliJ IDEA
 
-## Product scope
-### Target user profile
+## 3.Design
 
-{Describe the target user profile}
+### 3.1 Architecture
+The following diagram provides a rough overview of how BudgetBuddy is built
 
-### Value proposition
+![Diagram of overview of BudgetBuddy](diagrams/Introduction.jpg)
+
+`BudgetBuddy` is the main class of the application and directly interacts with the user, passing along the input
+into the Parser. The `Parser` creates a `Command` object depending on the user's input, which will be executed in
+`BudgetBuddy`. The `Command` object utilizes methods and the class present in the `Application Classes`, which will 
+be explained in more detail in the following sections.
+
+#### 3.2 Parser Class
+Make Class Diagram + Explanation
+
+#### 3.3 Ui Class
+Make Class Diagram + Explanation
+
+#### 3.4 Command Class
+Make Class Diagram + Explanation
+
+#### 3.5 Storage Class
+Make Class Diagram + Explanation
+
+### 3.6 Application Classes
+The classes present in this group of `Application Classes` refers to certain elements which serves a purpose more
+towards the `user` instead of application itself. They represent data of the user's financial transactions,
+including expenses and savings, along with mechanisms for organizing and managing this data in meaningful ways.
 
-{Describe the value proposition: what problem does it solve?}
+##### 3.6.1 Transaction
+Explain what it does
 
-## User Stories
+##### 3.6.2 Expense
+Explain what it does
 
-|Version| As a ... | I want to ... | So that I can ...|
-|--------|----------|---------------|------------------|
-|v1.0|new user|see usage instructions|refer to them when I forget how to use the application|
-|v2.0|user|find a to-do item by name|locate a to-do without having to go through the entire list|
+##### 3.6.3 ExpenseList
+Explain what it does
+
+##### 3.6.4 Saving
+Explain what it does
+
+##### 3.6.5 SavingList
+
+### 4. Implementation
+
+## 5. Product scope
+
+### Target user profile
+This product is for users who can type fast, and wishes to handle and track their current and future
+expenses on a singular platform.
+
+### Value proposition
+BudgetBuddy is faster and more efficient way to track and calculate current and future expenses if a user is able to
+type fast. It also provides the ability to deal with finances on a singular platform.
+
+## 6. User Stories
+
+| Rank | As a                          | I can                                     | So that I can                                 |
+|------|-------------------------------|-------------------------------------------|-----------------------------------------------|
+| 1    | user                          | add expenses                              | track my spending                             |
+| 2    | user                          | Categorise my expenses                    | manage my finances more efficiently           |
+| 3    | user                          | Plan my budget                            | Avoid overspending                            |
+| 4    | user                          | Edit or delete expenses                   | remove any incorrectly added items            |
+| 5    | User                          | Identify my largest spending category     | cut down on my spending                       |
+| 6    | user                          | allocate saved funds                      | know how much I will have left after expenses |
+| 7    | user                          | Have a section for children's allowances  | easily monitor their spending and teach them  |
+| 8    | user interested in financial literacy | access educational content                | Learn more about financial literacy           |
+| 9    | frequent traveler             | log expenses in multiple currencies       | accurately track my expenses across countries |
+| 10   | User                          | See what commands i can use               | I know how to use the application             |
 
 ## Non-Functional Requirements