Chapter I
What it means
The Khanda brings together three weapons in one sign. The central double-edged sword stands for knowledge of God, which cuts through falsehood and separates truth from lies. The circle around it, the chakkar, has no beginning or end, like God.
The two curved swords, kirpans, are called miri and piri: worldly power and spiritual power. They recall Guru Hargobind, the sixth Guru, who wore two swords to show that Sikhs must hold both together, serving God while defending justice in the world.
Chapter II
Where it comes from
The double-edged khanda is the sword used by Guru Gobind Singh in 1699 to prepare the amrit Sweetened water stirred with a double-edged sword, used in the Khalsa initiation. Glossary with which he created the Khalsa, the order of initiated Sikhs. The combined emblem in its present form became standard in the early 20th century, and it is now used on the Nishan Sahib and by Sikh institutions everywhere.
Chapter III
Where you see it today
The Khanda flies on the flag outside every gurdwara, appears on Sikh turbans, buildings and car stickers, and is worn as a pendant. It is the most recognised Sikh symbol around the world.