Difference between STLC and SDLC

STLC is software test life cycle it starts with 
1. preparing the test strategy
2. preparing the test plan
3. creating the test environment
4. writing the test cases
5. creating test scripts
6. executing the test scripts
7. analysing the results and reporting the bugs
8. doing regression testing
9. test exiting


SDLC is software or system development life cycle

phases are...
1. project initiation
2. requirement gathering and documenting
3. designing
4. coding and unit testing
5. integration testing
6. system testing
7. installation and acceptance testing
8. support or maintenance