No, not everyone qualifies.  And, yes, the determination of eligibility is based in part on work history.  The primary requirement for collecting SSDI is an injury or illness that meets the Social Security Administration's definition of a disability.  Follow this link to a post with more information about the type of conditions that qualify for disability benefits.

However, applicants must also be 'insured' to collect SSDI benefits, meaning the person has earned a certain number of 'work credits.'  Workers can earn up to 4 credits each year based on a scale that changes from year to year.  In 2009, workers will earn one work credit for each $1090.00 in wages or self-employment income. So, once a worker has earned $4,360 she will have earned her four credits for this year. Workers usually require 40 credits to qualify for benefits (with 20 of those credits earned in the ten years prior to the disability).  However the number of credits required depends on the age of the worker.  For example, a person who becomes disabled at the age of 27 would require 12 credits, earned within the six years prior to his disablity.  Please tell your friends about The Forum.