Difference between CMOS ICs and TTL ICs

CMOS stands for Complementary Metal-Oxide Semiconductor and TTL stands for Transistor Transistor Logic. When IC fabrication techniques were not well developed most of the digital IC's were fabricated using TTL technology, now in modern days almost all IC's come up with CMOS technology.

Simply put CMOS is advantageous than TTL in the following ways

1. CMOS has wide operating Range

2. Consumes less power than TTL

3. High Input impedance

4. Less Noise margins and high noise immunity 

5. Small form factor in some cases

That being said, TTL also has its own applications. Like TTL IC's have less propagation delay and are less susceptible to electrostatic discharge than CMOS IC's