At the end of the financial year, he would issue you what is called a Form 16. This Form 16 would have all the details of your tax deducted at source, including your total salary and your proofs submitted etc.
Form 16 is therefore essentially issued by your employer. You would need Form 16 to enable you know the amount of tax deducted by your employer and the same is useful while filing your tax returns.
Your employer will provide most of the key information required such as gross salary, perquisites, various allowances and deductibles.
From a tax perspective field 6, income chargeable under the head 'Salaries' is relevant in the form. This is your taxable salary.
Many individuals have complained about companies not issuing for 16. Please remember, you can take the matter up with the tax authorities. There have sometimes been reports that many companies do not even deposit the TDS cut from employees with the tax authorities, leave alone issuing a Form 16 to the employees.
This is a serious offense and the tax authorities are likely to take the companies concerned to task. It's extremely important that companies deducting tax at source deposit the same with the tax authorities.
There is also what is called Form 16A, but this more for companies and banks who cut TDS and issue a form 16A, unlike companies that issue Form 16.