What a bank actually does with your money, how interest is quoted, and how to set up a first account so saving happens without willpower.
Most students open one account, leave everything in it, and wonder why saving never happens. The structure of your accounts does more work than discipline does.
A checking account is for money in motion: debit card, direct deposit, bills. It pays little or no interest and is designed for frequent access. A savings account is for money at rest — it pays interest and is deliberately one step further away from you.
A high-yield savings account is simply a savings account at a bank that competes on rate, usually an online bank with lower overheads. The difference between a traditional bank's 0.01% and a competitive rate is real money on even a few thousand dollars.
APY (annual percentage yield) already includes the effect of compounding, which is why it is the number to compare between accounts. Rates on savings accounts are variable: they move with prevailing interest rates, so a rate advertised today is not a commitment.
A certificate of deposit (CD) locks money for a fixed term at a fixed rate, with a penalty for early withdrawal. It is sensible for money with a known date and wrong for an emergency fund, which by definition has no schedule.
Deposits at an FDIC-insured bank are protected up to $250,000 per depositor, per bank, per ownership category. If the bank fails, that money is made whole. Credit unions carry equivalent NCUA coverage.
Investments are not deposits. Money in a brokerage account is not FDIC-insured against losses — SIPC coverage protects against a broker failing, not against markets falling.
Once a buffer exists, money beyond it can go to work — investing basics. See also credit & credit scores or the curriculum overview.