At the beginning of the Paleolithic Age, humans were still living in caves. By the end of it, they were starting to form towns and develop agriculture.
The Paleolithic Age or Old Stone Age spans from roughly 2,000,000 BC to 10,000 BC. It was followed by Mesolithic (Middle Stone Age), which lasted until 5,500 BC and Neolithic or New Stone Age, which ended in 2,500 BC. It was marked with the inventions of the first tools and weapons that helped early humans survive their harsh and unforgiving environment filled with large predators.
Geologically, the Paleolithic Age coincides with the Pliocene and the Pleistocene. The Pliocene was marked with constant continental drift. It was at Pliocene that North and South America became connected, and the Mediterranean was created by the collision of Africa and Asia. Ireland separated from Britain, which was covered by glaciers.

The Paleolithic Age is one of the longest periods in human history, covering almost 2,000,000 years. The changes that happened during The Paleolithic were gradual. In the beginning, human population was mostly concentrated in Eastern Africa. By the end of it, humans have spread throughout Europe and Asia and have crossed Beringia land bridge into Americas. It is divided into Lower, Middle, and Upper Paleolithic Age and marks the final stages of the human evolution. It was during this age that Neanderthals went extinct and modern Homo Sapiens became the dominant species of the humans.
Most humans during the Paleolithic Age were hunters and gatherers. Their diet was limited to what animals they could hunt and fruit and berries found in nature. The first primitive spears allowed humans to pursue bigger pray, even organizing large hunting parties that were able to bring down even mammoths, whose extinction coincides with the end of the Paleolithic.

The first tool made of stone were knapped, meaning chipped from the stone and obsidian. In the later period, tools and weapons were made form other materials as well, including bone, wood, and leather, but very few of those survived.
The nature of hunters-gatherers society left humans with plenty of free time, something later agricultural societies lacked. This led to the first appearance of art in the form of cave drawings, primitive jewelry, and rock art. The first religious rituals were also created during the Paleolithic Age, mostly for burial purposes.
Source: historyinanhour.com