1. **Punch cards** – physical cards with holes. Early computers read data this way.![[Screenshot 2025-07-23 at 12.08.22.png | 400]]

2. **Magnetic media**:
    - First: **Floppy disks**
      ![[Screenshot 2025-07-23 at 12.08.48.png | 400]]
    - Then: **Hard disks** (faster, more storage)
      ![[Screenshot 2025-07-23 at 12.09.30.png]]
3. **1960s**: First **Database Management Systems (DBMSs)** created:
    - Charles W. Bachman developed the **Integrated Database System**
    - IBM developed **IMS**
4. **1970s**:
    - IBM created **SQL** (Structured Query Language)
    - Modern relational databases (RDBMS) were born
5. **20th century:** Many RDBMS's
	- ORACLE, Microsoft's SQLServer, IBM's DB2, MySQL, SYBASE...
	  ![[Screenshot 2025-07-23 at 12.10.02.png]]


##### Hadoop history
![[Screenshot 2025-07-23 at 12.16.32.png | 200]]
2005 - Started by ***Doug Cutting*** at Yahoo! 
[[Hadoop]] is an [[Open Source]] Apache project
Benefits: free, flexible, community-supported.