PDP7

The computer on which Unix was born.

• Flip-chip logic module-based processor
• 18-bit word-length architecture with ~35/40 basic instructions
• 10kb - 144kb memory
• I/O devices were teletypewriter, paper tape readers/punches, and magnetic tape drives
• weighed 500kgs
• Digital Equipment Corp shipped and sold 120 units in 1964 (at the price of USD 72,000)

Today, only 5 PDP-7s remain in the world. 3 in the US, one in Norway, and one in Japan.

Interestingly, the Unix v0, created on PDP-7 consisted of just 10k lines of C and 1000 lines of assembly code.
Even the stable version of Unix that ran on PDP-11/45 was just 44KB in size.