What is the basic infantry weapon used by the Israeli during the Arab Israeli War?

Depends on which one you're talking about. If you're referring to 1948, they had a hodgepodge assortment of rifles - Lee-Enfields, Mausers, Springfields, Garands, etc. In 1955, they adopted the FN FAL rifle, while many reservists were still armed with Mausers which had been rechambered for the 7.62x51 NATO cartridge. The FAL remained in production in Israel until 1980, but after the Yom Kippur War, began being phased out for the M16 and Galil. In 2006, they had M16s, M4s, Galils, and the Tavor TAR-21 is likely to have seen service, as well as the Negev light machine gun, Stoner SR-25, and other weapons.