The Oxford English Dictionary defines 'confidence' as being self-assured and feeling or showing self-reliance.
You have a whole range of tools - strengths, skills, abilities and strategies - available to you which will enhance your confidence. But sometimes you may not be fully aware of them.
By becoming more aware of these tools and the ways in which you can apply them in the face of life's challenges, you can build your confidence.
If you feel more is required of you than you are able to give when faced with a challenge, you are likely to feel less in control, more anxious, more helpless and more stressed.
Being fired, failing an exam or being rejected by someone tends to dent confidence because in all these situations you're at the mercy of someone else - you feel powerless.
Less Control > More Anxiety > Less Confidence
The good news is, if you focus on your strengths, your skills and your general ability to cope with the situation (even if you can't change it), your feeling towards the challenge of moving forward is likely to be much more positive.
This holds true even when you're facing a scenario you haven't encountered before, or when you're in a familiar situation that you didn't handle so well in the past.
More Control > Less Anxiety > More Confidence
It's not unusual to feel confident in some areas of your life but less confident in others. This might be:
In your personal relationships - romantic or otherwise.
At work - talking with your boss or adapting to a new job.
When you're with your family or when you're encountering new people.
For example:
A successful business person may find it difficult to relate confidently to a partner in a close relationship.
A skilled football player may lack confidence at the prospect of becoming coach.
An actor who will quite happily perform on stage in front of an audience may become tongue-tied when faced with a stranger in a bar or at a party.
And an adult who feels perfectly confident with their friends may well find it difficult to stop their parents treating them like a child.
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The above is part of the Introduction to the 'Get Confident' Online Course - see the BBC website for the full course
http://www.bbc.co.uk/health/confidence/learn/