Help me understand these 401k terms

401(k) - Pre-tax Payroll deductions of up to 75% of your wages can be taken, Roth post-tax account is also available. 50% company match on every $1 up to 6% of your investment. Part-time and full-time employees are eligible to participate in the 401(k) the first of the month after working 30 days. Auto-enrollment occurs at 4% into Target Date Retirement Fund on 1st of the month following 60 days unless the employee takes alternative action, auto-increase each January to 10% maximum. Employees mu