Raspberry Pi Zero

Raspberry Pi Zero technical specification: 

• CPU:Broadcom BCM2835, which can run at up to 1GHz.
• RAM:512MB
• Power:5V, supplied via micro USB connector, drawing 160mA (even when connected to an HD display).
• Dimensions:65mm x 30mm x 5mm
• Video & Audio:1080P HD video output. Audio output via mini-HDMI connector.
• Storage:MicroSD card.
• Operating System:Linux, installed via NOOBS. 

More technical specification:

• SOC: Broadcom BCM 2835
• Core type: ARM 1176JZ2f-S
• of Cores: 1
• GPU: Videocon IV 1080p @30
• RAM: 512
• CPU Clock: 1 Gz 

Raspberry Pi Zero I/O: 

Micro SD card:

Raspberry Pi Zero comes with inbuilt SD card holder for providing space for OS and another program to execute.

Mini HDMI:

Mini HDMI port is provided for connecting external display devices to the board.

Micro USB:

Micro USB ports are provided for providing power and connecting external devices to the board i.e. keyboard, mouse.

GPIO:

GPIO pins are the most important part in any board Raspberry Pi Zero come with 40 GPIO pins so that you can interact with different sensors and devices. 

Composite Video:

There's an RCA composited video output via two (unpopulated) pins, so you can hook the Pi Zero up to older display equipment that accepts a phono plug as an input.

What model Zero don’t have:

The only de-merit that model ZERO have is wireless connectivity like Bluetooth or Wi-Fi or Ethernet. Model Zero don’t have inbuilt Bluetooth or Wi-Fi due to lack of space which is a major De-Merit in this board.