TDS Meaning :
TDS means TAX DEDUCTABULE AT SOURCE. It is charged on Base Amount.
TDS is tax charged by the customer who gets the services from Vendor or supplier. Here Customer is responsible to charge it and pay to the government.
Different types of TDS :
1) TDS on salary has to be deducted on salary paid to employee by employer if it crosses the tax limit. And pay to the government on or before due date.
2) In case of TDS on contractors or profession or others, there is slab that min tax, surcharge, education cess plus higher education cess, it is different and finance minister may change or keep same or remove in every year budget. Secondly you can deduct the TDS on bill amount while paying or if advance is paid.