What does it mean to express milk by hand?

Pumping by hand. Hand expressing means pumping milk from a breast without using a pump. The woman takes a warm shower or applies a warm cloth to her breast for a few minutes. Then she massages her breast by encircling her breast with both hands at the chest wall and slowly squeezing the breast in towards the nipple. After a couple of minutes, the breast will start discharging milk and this can caught in a cup.
Efficiency! Believe it or not, i did this myself! i found using a breast pump to be an inefficient and uncomfortable way to express breast milk. Knowing that i was returning to work at 3 months required me to find an alternative. I found hand expression (cup your hand around your breast way up high and then squeeze downward until the milk comes out) to be a very efficient option i could do anywhere.