vim

Window:

Switch window:

:sp
:vsp

Ctrl+w Ctrl+w or Ctro+w navigation keys

widnow move
Ctrl + W + R   - To rotate windows up/left.
Ctrl + W + r   - To rotate windows down/right.

You can use the Ctrl + W + navigation keys to change windows' position too
Ctrl + W L   - Move the current window to the "far right"
Ctrl + W H   - Move the current window to the "far left"
Ctrl + W J   - Move the current window to the "very top"
Ctrl + W K   - Move the current window to the "very bottom"

window resize
The easiest way:

Ctrl + w [n] [-|+|<|>] 

Ctrl + w = 


Buffer:
:ls - to list all file buffer
:ls! - to list all buffer
:b # - to move to the #th buffer
:bn - open next buffer
:bp - open previous buffer
Ctr+o and Ctr+p

Explore:
:E
:Ve
in explore, press:
t - to open in new tab
v - to open in vertial split window