basically what that extract says in plain english:
- you can store data in byte addressable locations.. i,e. a memory address FF
- it is non volatile and you can have many reads/writes using eeproms - typically they have a lifetime of around 10,000 writes/flashes
- for data that does not change indefinately such as constants, flash memory should be used, or you can refresh the eeprom to varify the data integrity... (this really doesnt apply for first
... data in eeprom is good for a few years or so, depending on the technology).. Refreshing eeprom basically puts a voltage accross the array such that all the data is completely erased and then rewritten to verify the integrity of the data. This should be done every X writes (stated in the datasheet) to remove stray charges that may build up after multiple writes, which could corrupt the data written.
The figures at the bottom state the environment for which the time stated in D124... (which is a microchip app note common for pics using the same eeprom technology) is true for... i.e. at this temp, humidity etc you need t refresh you'r e eeprom every Xmonths/years/whatever (this will be a long time... way way beyond the actual event if you were to program the pic now for a single write
... or how many writes you have before you need to refresh to be safe)
For more info look up "refreshing" and RAM... computers do this all the time to keep your ram in your computer happy as its volatile, i.e. the data is only good for so long before you need to refresh it otherwise you lose the data...
Hope this is useful