All perfect praise be to Allaah, The Lord of the Worlds. I testify that there is none worthy of worship except Allaah, and that Muhammad is His slave and Messenger.
The Salafi school is the Islamic school of thought that adopts a methodology based on following the path of the righteous predecessors. The righteous predecessors include the Companions of the Prophet, sallallaahu ‘alayhi wa sallam , and those who follow them in righteousness up to the Day of Resurrection. The followers of the righteous predecessors are found at all times, as the Prophet, sallallaahu ‘alayhi wa sallam, said that a group from this Ummah (nation) would always remain steadfast on the right path and continue to be triumphant against their opponents, and that he who let them down would not be able to do them any harm. The Prophet, sallallaahu ‘alayhi wa sallam, said that they would remain as such until the end of the world. [Muslim]
The Salafi school is moderate; they are neither like the Khawaarij who consider killing a sinful Muslim lawful nor the Rawaafidh school who judge the honorable Companions to be disbelievers. The Salafi school believes in the attributes of Allaah The Almighty that occur in the Quran and authentic Hadeeths of the Prophet without distorting their wordings or meanings, nor denying them, nor asking how they are, nor drawing any resemblance between Allaah and any of His creation.
The Salafi school are far from those who believe in incarnation and unity of the Creator and creation, that is, the belief that Allaah The Exalted dwells within any of His creatures.
The Salafi school are far from the Sufi school that worships the graves and offers vows to them.
In brief, the Salafi school is the way the Companions and the rightly-guided Caliphs followed; other schools have deviated from this way. Nevertheless, it should be noted that these schools are not similar, rather they differ according to how close or far they are from the way of the righteous predecessors.
Allaah Knows best.