Grid 1

grid-template-columns: auto auto auto;

Three columns, auto-resizing.

Grid 2

grid-template-rows: 3fr 1fr 1fr 2fr;

Rows (or columns) can have weighted dimensions, by fraction amout (fr). Also auto-resizing.

Grid 3

grid-template-columns: repeat(auto-fill, minmax(200px, 1fr));

grid-gap: 12px;

A responsive auto-fill layout with a size limit.

Grid 4

grid-column-start: 1; grid-column-end: 3; grid-row-start: 1; grid-row-end: 2;

Set the starting and ending point for columns and rows

Grid 5

grid-template-columns: 120px 240px 120px 240px;

Set fixed dimensions for each column.