1920s

• One-time pad cypher (a key form of cryptology used in World War 2)

1930s

• Discovery of radio waves emanating from the center of the galaxy

• Stereophonic recordings and transmission

• First electronic speech synthesizer

1940s

• First photovoltaic cell

• Invention of the transistor

1950s

• First binary code systems

• First solar cell

• Concept of the laser described

1960s

• First continuous light laser

• Invention of the Metal Oxide Semiconductor Field Effect Transistor (MOSFET)

• Discover of Cosmic Background Radiation (Basis of Big Bang Theory)

• Invention of the Charge-Coupled Device (CCD) used in imaging cameras

1970s

• C Programming Language

• UNIX Operating System

• First single-chip 32-bit microprocessor

1980s

• TDMA and CDMA digital cellular telephone technology

• Laser cooling

• First fiber optic transatlantic cable

The above is a highly abbreviated list of accomplishments. 

All of these accomplishments came from one source – AT&T Bell Labs.