Python Anaconda: should I use `conda activate` or `source activate` in linux

So I am used to typing source activate <environment> when starting a python Anaconda environment. That works just fine. But when I create new conda environments I am seeing the message on Ubuntu 16.04 to start the environments with conda activate instead. Besides the errors about how to set up my shell to use conda activate instead, I am still not clear on what is the difference between source activate ... and conda activate ... Is there a reason to change? Does anyone know the difference between these two commands? Thanks.

As of conda 4.4, conda activate is the preferred way to activate an environment. Generally, you won't find too much of a difference between conda activate and the old source activate, except that it's meant to be faster, and work the same across different operating systems (the latter difference makes conda activate a huge improvement IMO).

From the docs, regarding the release of conda version 4.4.0 (released December 2017):

>conda activate: The logic and mechanisms underlying environment activation have been reworked. With conda 4.4, conda activate and conda deactivate are now the preferred commands for activating and deactivating environments. You’ll find they are much more snappy than the source activate and source deactivate commands from previous conda versions. The conda activate command also has advantages of (1) being universal across all OSes, shells, and platforms, and (2) not having path collisions with scripts from other packages like python virtualenv’s activate script.

Here is one difference I found. source activate can be used at the beginning of a bash script to load conda environment, whereas conda activate would give me an error:

CommandNotFoundError: Your shell has not been properly configured to use 'conda activate'.

This makes a huge difference to me since I often submit bash jobs to cluster and source activate is the only way to change conda environment.

Please correct me if anyone can use conda activate in a bash script.

I am not sure who might find this useful, but if

1. Your terminal lags due to the addition ">>> conda initialize >>>" in your .bashrc, then you decide to remove it and add anaconda to the path. If that is the case, then "conda activate env_name" won't work, but "source activate env_name" will work, and then after that, you can use either source activate or conda activate. If you close the shell then to activate the environment again use "source activate env_name"
2. FYI, removing ">>> conda initialize >>>" from my .bashrc file has speedup my terminal and it doesn't lag anymore and I just default in using "source activate env_name"
3. I have Ubuntu 20.04, conda version : 4.10.3, and conda-build version : 3.21.5