Block and parcel (Gush / Helka)
In short
Every piece of land in Israel is identified by a block number and a parcel number, like an ID card. With them you can pull a Tabu extract, check the zoning plan and order an information file.
The professional explanation
Blocks and parcels were set in land settlement (Mandatory and Israeli) and are updated by reparcelation plans and registration plans. A sub-parcel identifies an apartment in a condominium.
A parcel number may change after a reparcelation plan: the "old" parcel is cancelled and new ones registered. Always compare the extract, the plan drawing and the block map.
To find block and parcel by address use govmap (Survey of Israel), the Planning Administration site or the municipal GIS.
Example from the field
In a Sharon agricultural land deal the memorandum quoted a parcel number cancelled by a new registration plan. Checking the current block map showed the seller held a smaller new parcel than presented.