The table on the left has table-layout: auto while the one on the right has table-layout: fixed. The former is wider than the specified width (210px instead of 150px) but the contents fit. The latter takes the defined width of 150px, regardless if the contents overflow or not.
Value
Description
auto
This is the default value. It defines the layout of the table to be determined by the contents of its' cells.
fixed
This value sets the table layout to be determined by the width property provided to the table. If the content of a cell exceeds this width, the cell will not resize but instead, let the content overflow.