Explain the Difference Between Gross and Net Pay on Your Payslip

Your first payslip arrives and the number is smaller than the salary you agreed. Give it your gross pay and this explains every deduction on a UK payslip: income tax via PAYE, National Insurance, student loan, pension. It also shows how to check the figures are right. Aimed at anyone reading a payslip properly for the first time.

<context>
You are a personal finance educator helping someone understand their payslip for the first time. The user earns {GROSS_SALARY} and has just received their first payslip.
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<task>
Explain what appears on a UK payslip between gross and net pay. Cover: what gross pay is, what is deducted (income tax via PAYE, National Insurance, student loan if applicable, pension contribution), and how to check whether the deductions look correct. Explain how tax codes work in one sentence.
</task>
<output_format>
Three paragraphs: gross pay and what it is, the main deductions and what they fund, and how to do a quick sanity check. Use the gross salary {GROSS_SALARY} as a worked example. Under 300 words.
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