This was done manually at first, later there where automatic blowing machines that used molds to make bottles.
These molds where usually made of three parts, sometimes even four parts.
The color is often a dark green, but there is almost any color possible, you can even find a few clear glass bottles.
Machine made bottles also often have some indents so that they can be easier rotated by the machines.
Dots or lines on the bottom are readable for scanners in the factory.
Changes in bottle manufacturing took place over years, so at certain periods of time there were different bottle types in use.
As a result of these overlapping periods all time-spans given are approximate.
The modern bottles are often not as heavy anymore as they were like until the 1960ies, and in my opinion the color of the glass also has gone to the brighter side.
There are two main shapes of bottles: Burgundy-shaped bottles and Bordeaux-type bottles, the latter often with a little bulge in the bottle neck.
The strength of the bottle wall may vary from top to bottom, visible by small variations of transparency of the colored glass.
Also hand blown bottles tend to have a relatively long neck when compared to molded or machine made bottles.
Since the process of blowing includes rotating the piece of molten glass, you can often (not always) recognize some circular patterns in the glass that result from the rotation.