To clear all definitions or to reclaim resources used by the kernel, you may want to restart it.

Using the Menu...

Quit the kernel

Quit the kernel by choosing Evaluation Quit Kernel "kernel name", where kernel name is typically Local:

Restart the kernel

Any subsequent evaluation will automatically restart the kernel:

In[1]:=
Click for copyable input
Out[1]=

Programmatically...

Quit the kernel

Quit the kernel by evaluating Quit:

Restart the kernel

Any subsequent evaluation will automatically restart the kernel:

In[3]:=
Click for copyable input
Out[3]=

Using the Menu...

Quit the kernel

Restart the kernel

Any subsequent evaluation will automatically restart the kernel:

In[4]:=
Click for copyable input
Out[4]=

Programmatically...

Quit the kernel

Quit the kernel by evaluating Quit:

Restart the kernel

Any subsequent evaluation will automatically restart the kernel:

In[6]:=
Click for copyable input
Out[6]=

Programmatically...

Quit the kernel

Quit the kernel by evaluating Quit:

Restart the kernel

Any subsequent evaluation will automatically restart the kernel:

In[8]:=
Click for copyable input
Out[8]=

Notes

If a notebook has Dynamic content, the kernel may restart before you perform an explicit evaluation.