Help, aid, assist, succor agree in the idea of furnishing another with something needed, especially when the need comes at a particular time.
Help implies furnishing anything that furthers one's efforts or relieves one's wants or necessities.
Aid and assist, somewhat more formal, imply especially a furthering or seconding of another’s efforts.
To succor, still more formal and literary, is to give timely help and relief in difficulty or distress: Succor him in his hour of need.